Solar Powered GroPockets.
Watch this two-minute video on solar powered GroPockets.
See the next post down for more info re the GroPockets.
18 reasons why air lift pumps make so much sense and why you should seriously consider this methodology for your Aquaponics system. (Yes your home Aquaponics system will benefit as well)
Here is the list.
1. No more submersible pumps.
2. Lower install cost.
3. No need for additional Earth Leakage Safety cut out switch. (GFI outlet) Higher safety threshold.
4. So simple even school children can do the install.
5. Virtually maintenance free.
6. No moving parts. K.I.S.S.
7. Easily pump solids.
8. Stock separation.
9. Increase water lift.
10. Save electrical energy cost.
11. Go way beyond common lift provided by a regular submersible.
12. Pump higher than ever before.
13. Turbo drive your water pump.
14. Turbo drive aeration.
15. Verticals easily supplied, such as Zip Grow towers or Greenlife Pocket towers. (this feature alone is amazing)
16. Repair and replacement costs greatly reduced.
17. Very long service life.
18. Never run dry.
There is a few more reasons that will be expanded on in our one day Air Lift seminar with Glenn Martinez Brisbane Friday 6th March.
Glenn will show you how to make it work, has plan books showing exactly how to do it at your place. Glenn's air pumps will revolutionise Commercial Aquaponics.
PS.....Class was run on Friday 6th March and was just fantastic. WE have filmed the event and will soon post the edited film for our Gold Members to see.
Look at this disgusting mess.
The possibilities of killing everything in the Aquaponics system is very high starting with pump failure, quickly followed by fish deaths. OK, it will take a bit longer to kill the plants but not too long to kill all the fish.
The possibilities of killing everything in the Aquaponics system is very high starting with pump failure, quickly followed by fish deaths. OK, it will take a bit longer to kill the plants but not long at al to experience fish deaths.
So, what is the problem?
Very simple, = poor maintenance regime.
So many home systems in particular, suffer from poor pump maintenance. The pump should be looked at weekly. Just give it a quick look over to remove any debris that may have collected on the filter screen. Quickly remove and we are all good. This is particularly important for systems being run outdoors, that is, not in a protected cropping structure such as a greenhouse.
Leaves and even dead plant roots coming down from the raft system to the sump and finally onto the filter screen of the pump. In the photo above you can even see a lonely clay pebble that has found its way onto the pump.
Commercial farm systems need to be even more vigilant. A well-organised regime of maintenance should be followed. Checklists for farm staff should definitely include physically looking at the pump or pumps. Not good enough to walk past, "Yep, water is moving and I can hear the pump".
Stop, take a careful look and if necessary clean the filter screen.
Of course, you will not have any of these problems if you employ an air-lift pump.
Immediately following our March the second 4 day Master Class we will have Glenn Martinez from Olomona Gardens Hawaii here to teach and demonstrate a full day of airlift pumps. That's right, pumping water, loads of it using a regular air pump. That is Friday March 6, 2015 here at Brisbane. We are flying Glenn down to Australia to demonstrate airlift pumps. This is a rare opportunity to meet Glenn one of the very few innovators in the world of Aquaponics.
Glenn will, on the day, actually build several different configurations of pumps. These are real and are capable of moving lots of water in a very economical way. No more pump blockages.
Book now for this standalone one-day event.
If you are coming to the Master Class make sure you book to stay for this fantastic learning experience.
The area needed is arbitrary because it depends very much on how well you manage your Aquaponics garden, the types of crop grown and so on. Also, efficiency improves as the garden gets bigger. What crop to grow, how many to plant, when, how often? Your local climatic conditions play a major part in the equation. Serious planning and attention is required to make it happen.
It is generally accepted, by working a regular soil garden you will need 30 sqm (320 sqf) to feed a typical family of 4. That will then be 7.5 sqm (80 sqf) per person. I believe that an Aquaponic garden is much more efficient than a regular garden so the growing area required will be less.
We have spent a long time thinking about this question and observing what we can and have achieved over the last 8 years and we believe 23 sqm (250 sqft) of AP gardening space is needed to feed a family of 4.....with all the skill and attention needed to make the garden sing. So, that is approx 6 sqm (62 sqft) per person.
Aquaponics is still a garden, and successful gardening requires time and dedication.
This INDY 23 plan set is the result of 8 years of practical AP, full time 7 days a week. 23 sqm (250 sqf) of growing area spread over three different growing methodologies to produce a wide variety of produce and a realistic number of fish dinners.
If you want to be serious about food production for your family this is the minimum required.....sorry. And if you seriously do want to produce a really big chunk of your family food needs, a few other things like a half dozen egg laying chickens, some space for fruit trees and so on will need to be added to the project. Let's take a realistic approach to home grown, chemical free, nutrient dense food.
But, to move toward this goal step by step, and to produce what you can, to acquire the skills needed takes time and effort. Start to produce what you can in the time and space you have available to you.
Take the time to acquire good sound knowledge. Frankly, watching a dozen or so You Tube clips made by people who started Aquaponics a few weeks before probably won't cut it...sorry. Buy a book or a DVD from a good reliable experienced source. Trouble is we see on the internet people making crazy claims, no doubt we have all seen them, "10 times the vegetables, in half the time, twice as big." 2000 lbs of vegetables from a kit made out of a couple of old IBC's, a few bits of pipe all held together with string.....
The "armchair generals"....
The magic about Aquaponics is,
#1 Aquaponics is an ECO system and the veggies and fish produced are clean nutritionally rich family food. Much, much better than "Organic".
#2 It is more efficient than a regular garden because the plants have delivered to them water and nutrients continuously 24/7. The fish grow up in a healthy protected environment.
The CHOP system is an acronym for “Constant Height One Pump”. This is the most efficient way to run an Aquaponics system.
The basic principal is to use the force of gravity to assist us where possible. This brings high efficiency in electric power consumption and plumbing design.
The CHOP system is also better for the health and wellbeing of the fish, as it means there is more water in circulation that brings stability in both temperature and pH. Because the fish tank is always full of water, the fish are safe if something goes wrong with plumbing or pump. The auto siphon system is an automatic way to flood and drain the media beds without the need to employ float switches or timers. The system is lower maintenance than older system designs that required float switches, timers and a second pump.
CHOP or Constant Height One Pump has been adopted by Aquaponics enthusiasts around the world and its popularity has demonstrated the methodology’s effectiveness. The other variant CHIFT PIST (Constant Height In Fish Tank. Pump In Sump Tank) runs in a similar way. In fact CHOP as an acronym was coined because the acronym CHIFT PIST was thought to be a little clumsy and crude.
Constant height in the fish tank is important in that we want to have a system design that ensure that the fish tank cannot be run or pumped dry should something go wrong, such as a pipe failure somewhere in the system. If something goes wrong and the sump is pumped dry and or the media beds run dry, it is not desirable but it is not a disaster as would be the case if the fish tank is pumped or drained dry.
One pump is important from an economical operation point of view. So, our plumbing design is such that all the water can be moved around to all parts, in the volumes we require for each section of the system, by the one pump.
The pump resides in the sump. All pumping is done from here. I like to call the sump “Grand Central Station”. It is the central meeting point of all the water flow in the system. The water is pumped from the sump to the fish tank, and from the fish tank the water runs by gravity to the media beds. The auto siphon or timer allows the bed to fill then drain back down to the sump. In this way there is only one regulated flow around the entire system and that flow rate is dictated by the auto siphon/s.
CHOP system methodology allows us to use the absolute minimum of power to move the water around. Aquaponics systems are perfectly natural systems except we have to move the water, and we can only do that with pumps of some sort or another. So, over a period of time we have strived to get our pump size down and enjoy a very minimum of power usage. In CHOP systems the water flow in one direction is done by gravity and in the other direction it is removed from the sumps back to the fish tank by the most efficient pump possible.
Originally, our systems had two pumps in them all the time, one was required to move the water out from the fish tank and one to move it back and we quickly discovered that that was just a waste of energy. This is another advantage of the CHOP system.
Chop #2 is a further and much improved variant to the standard CHOP methodology. We noticed a problem with water levels whilst working on a small commercial CHOP system we were commissioning. Running the feed water from the fish tank via a filter then on to be distributed to each media bed by gravity flow was problematic. If all the beds were not precisely level with each other the lower bed/s would receive more water than the others. This could be regulated with valves on each bed water inlet. This works fine on small systems, but the larger the system the larger the pipe work needs to be in order to accommodate sufficient water flow by gravity. Evenly distributing water by gravity to six beds that together were 30 meters (98’) long was near impossible.
We needed to refine the process for our client, so we came up with a solution that has been working well for several years, and now on many thousands of home systems and a good number of commercial systems. Pumping the water to the media beds, positive pressure delivery instead of gravity delivery. It is relatively easy to ensure even distribution to each bed and also to the most distant bed delivering the water by positive pumped, or header tank pressure. The system water is delivered to all points under pressure, either by pump or from a header tank. The pump is located in the common collection and distribution point; the sump. All the water arrives from the various parts of the Aquaponics system into the sump, all water leaves from the sump to the various parts of the Aquaponics system.
Water is delivered, as necessary, in various loops to the media beds, the raft beds, the fish tank and if included, to the mechanical filter. The water is collected from each loop or system segment back to the sump. The water is delivered to each loop or system segment from the sump under pressure either by pump or header tank. The water flow is regulated to each part of the overall system by the use of a simple valve or tap. Very accurate flows can therefore be achieved. CHOP 2 allows the operation of each element of our Aquaponics system at its ideal flow rate. This multi loop arrangement allows much more flexibility in plumbing design and precise flow control through the various elements of the overall Aquaponics system.
The question is often asked if there is a need to add mineral and nutrient supplements to Aquaponics systems. The answer is yes if you want to have nutrient dense vegetables.
In the very beginning, I advocate the use of a seaweed extract such as Seasol for an initial boost in a new system. It gives the new system something to work on and acts as a tonic for the Aquaponics system aiding in the establishment of the beneficial bacteria. It is a very gentle and safe way to get your Aquaponics system started.
A new Aquaponics system needs time to develop all the bacteria and microbes that will convert and release the necessary nutrients for good plant growth.
Aquaponics systems closely mimic nature in the way they handle and provide nutrients for the plants. Eventually there is a myriad of bacteria and other microbes that do their job, just as they should in a mature Aquaponics system.
The job of the two main beneficial bacteria in converting the ammonia produced by the fish to nitrates is very obvious. They are established in a new Aquaponics system usually within a few weeks. It takes time for all the other natural processes to develop and establish.
This is the amazing thing about Aquaponics . The way it becomes so balanced and complete. Never forget, the beauty of Aquaponics is that it is an ECO system. Aquaponics utilises natural processes. The beneficial bacteria, fungal hyphae, protozoa, and nematodes will take up residence in the gravel media beds and do their job of creating nutrients and having them distributed around the system by the moving water
I also advocate the use of "worm extract" or "worm juice or tea" as it is sometimes known. This is done to help “kick start’ the mineral and trace element build up in your new system. Worm tea is not always available to you so the Seaweed extract is a good thing to use in getting your new Aquaponics system up and running.
It should be applied at the rate of a CAP full a day. This can be continued right up to and past when you add the new fish to your Aquaponics system. Seasol will not harm the fish. We have tested and used Seasol for more than six years in our Aquaponics systems and are very satisfied with the results. Natural organic mineral supplements like Seasol work slowly and are not like chemically derived fertilisers.
Seasol or Maxicrop in the USA if you cannot source my favorite product Seasol. Seasol can be applied once every month or two to a mature system and as above for a new system. This will assist in a balanced mineral load and as a tonic for the Aquaponics system. It is a good idea to add it at the grow bed water entry point and allow it to peculate down through the grow media and make it's way around the system carried by the water.
You may find it a good idea to add a half a teaspoon of Chelated Iron to one of the grow beds once a month. Iron deficiency is often encountered in new systems. This is most often a symptom of “Nutrient Lock Out” caused by pH above 7. As pH stays above 7 nutrients are locked up and are not available to the plants even though they may actually be in the system.
Aquaponics systems run best at pH 6.2 to 7.0.
If adding Iron, just use a little water to wash the Iron down in amongst the grow bed media. The Chelated iron can also be added straight down into the water beside the auto siphon device.
This way the iron will be dispersed more slowly around the bed/s. Even though it is added to just one bed, it will find its way around through the entire system.
Potassium and Calcium are also needed in Aquaponics systems. If feeding your fish on commercially available pellets these two elements are often in short supply in your aquaponics system. Once again, potassium is present in Seasol.
Another way to boost trace elements and particularly potassium and iron is to add some raw molasses to the system water. Two tablespoons per 1000 ltr (250 gal) It will turn the water a little dark in colour but will clear after a few days. Molasses is also a sugar so the beneficial bacteria will also get a boost because of the addition of molasses to your Aquaponics system. It is perfectly safe for your fish
These two elements are easily supplied as part of pH control / adjustment.
Murray Hallam's Practical Aquaponics.
Aphids are one of the more difficult plant pests to deal with in an Aquaponics fish garden. How do they get into the garden? Usually they are brought in on plants, seedlings that you purchase from a nursery, or carried there by ants from some nearby garden.
Evidently there are around 4000 different types of aphid and at times I am sure most of them have been in my garden at some time!
Controlling them is a little difficult in Aquaponics because we do not have available to us sprayable material such as insecticides that would be commonly used on the regular farm or garden. We really don't want to use that kind of pest management for a couple of reasons.
1... We want to get away from using dangerous chemicals on our food supply.
2... If we spray that kind of poison we will most likely kill the fish.
3... Poisonous sprays kill beneficial insects as well as destructive insects.
One spray able solution is Neem Oil. This product is an oil extracted from the neem tree which is native to India. Neem oil is considered to be a non toxic solution and is used as one insect control mechanism on some organic farms. Neem oil is not very fish friendly so if it is intended to spray this material on your aphid infected plants then great care must be taken to prevent the oil spray drift getting into contact with the water. This is, in practice, very difficult to do. We spray garlic concentrate, chilli spray, molasses spray regularly in summer but find that these methods help but are not nearly as effective as the use of beneficial insects.
The best way to control aphids is by the use of “IPM” or Integrated Pest Management. IPM aims to suppress pest populations below the economic injury level (EIL)[i]
Seen here is an aphid infestation that is under attack by parasitic wasps Aphidius ervi
These wasps are multiplying rapidly to cope with the aphid infestation.
In keeping with the underlying mantra of our Aquaponics Garden being an ECO system it would be counterproductive to find some poison to kill the aphids for example, because at the same time we would very likely also despatch any beneficial insects. Particularly threatened by these "poison" approaches is the honey bee, and all would agree that would be disastrous.
The most "all purpose" beneficial insect is the Green Lacewing.
As the common name implies, adult green lacewings are green, with four clear wings. Adult female lacewings live for approximately three or four weeks and lay up to 600 eggs. The eggs hatch and the insect goes about its task of dealing with a variety of garden pests such as,
Aphids (various species)
Twospotted mite Tetranychus urticae
Greenhouse whitefly Trialeurodes vaporariorum
Scales (various species)
Mealybugs (various species)
Moth eggs and small caterpillars
So they are pretty handy to have around the greenhouse.
These can be purchased fairly inexpensively and do a great job. Visit the “Bugs for Us” website for detailed information on how to purchase these little critters and release them in your garden or farm.
Here is another insect that we have in our Indy 23 greenhouse doing its share of work on the resident aphid population.
The Striped Ladybird Beetle.
There are 27 main groups of this little beauty that are a very important part of our Integrated Pest Management approach in Aquaponics gardening either for home or in a commercial farm setting.
See more info about these wonderful little creatures at Brisbane Insects.
A premier Aquaponics event will be held in Spring Texas, Sat - Sun 9/14/13 - 9/15/13 and Mon - Tue 9/16/13 - 9/17/13
Aquaponics Institute team with Murray Hallam will present Home Aquaponics instruction at its best. There will be two x two day sessions. Choose the two day session that suits you best.
Discover Aquaponics –
Includes; What is Aquaponics. Aquaponics description/history. What you can grow. Plants. Fish. The Aquaponic advantage. Comparison, Hydroponics, Aquaculture. Is Aquaponics Organic.
Cycling a new system –
The nitrogen cycle. Cycling without fish. Cycling with fish.
Recycling nutrients. Environmental parameters.
System Parameters –
pH. Dissolved oxygen. Temperature. Conductivity (EC)
Water Chemistry –
Managing system chemistry. Nutrient origins.
Protected Aquaponics –
Why protect. Protection criteria. Climate control. Structure types. Geodesic domes. Hoop houses. Heating and cooling methodologies. Layout and planning.
Dragon Heaters –
Wood burning combustion chamber technology.
Practical Workshops –
Dragon heaters. Greenhouse system inspections. Backup systems.
Types Of Aquaponic Systems-
Media Grow Beds. Nutrient Film Technique. Deep Water Culture. Wicking Beds.
Pumps. Plumbing. Siphons. Timers. CHOP. CHOP 2. FloMedia. Filters. Clarifiers.
Swirl filters. Canister Filters.
Fish and Plants-
Fish diseases. Treatment.
Integrated pest management. Common plant diseases.
Nutrients balance/shortfall. Compost. Vermiculture. Grow bed health.
Which species of fish. Fish food.
Practical Workshops –
Home system build. Plans. Liner. Specifications.
Water testing. Aeration devices. Fish handling.
Seed raising. Planting. Pruning. Buffering the system.
Aquaponics Institute team with Murray Hallam will present Home Aquaponics instruction at its best. There will be two x two day sessions. Choose the two day session that suits you best.
Grid Power is very convenient for powering our every need including Aquaponics, but how reliable and affordable will it be into the future?
It is the desire of almost every Aquaponics operator to ultimately run their system independently of the mains power grid. Just how reliable and affordable will mains power be into the future is the question on my mind. Now that I have well established Aquaponics systems, getting off the mains grid power system is just another step in the journey towards self sufficiency. I have been dreaming about this since I don’t know when. Just where to start and at what level? As one quickly discovers, it can become an expensive exercise.
The mains power grid is just so convenient, plug the pump and aerator in, switch on and that is all there is to do. So why take on such a project?
Here are a few of my reasons,
1. Sick of pump difficulties. Pumps fail or shut down for a number of reasons and many (but not all) of the reasons will be eliminated when going “off grid”
2. Mains power grid outages due to storms, car crashes, mains power grid system maintenance, or for a variety of other reasons.
3. Off grid will be the ultimate backup system.
4. Sick of safety switches tripping out. Submersible “pond” type pumps often, over time develop earth leakage problems which will cause the safety switch (earth leakage) to shut the pump down.
5. Power bills going up and up. The cost of mains electricity has risen by more than 35% in the last 18 months and is tipped to double in the next 12 months or so. Some States of Australia are tipped to go even higher
6. I just want to be more independent – self reliant and get off the grid eventually – a.s.a.p.
As I see it there are different levels of power independence.
1. Grid connected solar panels.This arrangement will supplement the running cost of
your Aquaponics system. It will not provide any back up ability because if the mains power grid goes down then you have no power from the solar panels. A small battery back up system triggered by a Power Fail Switch is an absolute must in this instance. This is possibly the best first step for most home based Aquaponics systems. It gives you a tangible benefit immediately both for your home and your Aquaponics system.
2. A stand alone solar panel with a battery of sufficient capacity to run your system on a bright sunny day and at night your pump/s are switched off so that only an aerator runs from the battery. A stand by generator set would be necessary in the case of prolonged inclement weather or an auto switching device to switch to mains power once the solar panels stop delivering sufficient power to the battery.
3. Solar array and battery bank of sufficient size to support your Aquaponics system round the clock and for several days in the event of inclement weather. To be totally independent of the grid power a suitable generator set would be needed with auto start once the battery voltage dropped to a pre set level.
A couple of years ago I installed a solar grid connected solar system on my house roof. It is only one kilowatt which I have discovered is just nowhere enough for the average household to make a noticeable difference. It works just fine and it does help, but is not enough to completely offset my household power requirements.
I really want to be completely independent of the power grid system both at home and in the workshop / Aquaponics garden area. I am aiming for a large solar array with a substantial battery bank and a auto switching diesel generator set. Ultimately, I will also fit into the system some wind generated power. I have figured that I can move towards this goal step by step as funds and time allow. A really well functioning stand alone solar system can be built piece by piece with proper planning.
My project has had a kick start with the acquisition of a decent battery bank courtesy of a client who was moving house and upgrading his “off grid” system. The money I paid him for the batteries was so little that it can only be categorised as a gift. Thanks mate !!!!
I have since discovered the shortcomings of a large battery bank connected to a inverter. Most , if not all inverters are set to cut out/switch off when the battery voltage drops to 10 volts. Usually there is a warning buzzer at 10.5 volts. This is done to protect the battery bank from discharging to far and thereby damaging the batteries.
This governs the the length of time your pump/s can run during the night or when there is a succession of very low light days such as during heavy rain. The load on my battery bank is a total usage via the inverter of 420 watts at 240 volts. (7 pumps at 60 watts each).
I have found by observation that this usage will run the battery voltage down to 10 volts in around 7 hours at which point my inverter switches all the pumps off.
Not very long really. It is therefore not good for me to run my systems, at this time, off my battery bank, charged only by solar panels during the day. There is not enough battery storage to see it through the night until charging from the panels begins again shortly after sun-up.
The energy from the sun needs to be utilised in another way to store up energy for use during the night.
Right now I am using my battery bank strictly as a backup system. There is only a fan and couple of aerators running via the inverter. I have rewired it to a 24 volt system and have run power from the battery bank at 24 volts DC to all the fish tanks. Each group of tanks (3 groups) has it's own Power Fail Switch that will switch on a 24 volt x 500 gph pump in each fish tank if the mains goes off at any time. All 7 pumps draw only 1 amp each , so a total load of 7 amps. This will run for around 72 hours before the battery bank voltage drops to 10 volts.
For future posts.
Pump failure not related to power outage. How to take care of that possibility.
Choosing a tank suitable for aquaponics is probably a no brainer. Many people grab the first thing that suits their budget, but not all tanks are the same and some can positively damage your health and kill all your fish. We take a look at choosing the best tanks for your budget with Aquaponics guru Murray Hallam. The good, the bad and the ugly. Got 15 minutes? Its worth a listen.
Listen to the audio podcast....
Ecofilms: Murray – Tanks! Its one of the things that most people when they get interested in aquaponics – start looking around for a tank and I know you’ve got your favourite tanks that you like to talk about but there are many ways of putting fish into a system. Run through some of the various methods people use to get started in aquaponics?
Murray Hallam: Well there’s various levels that you can start at aquaponics. There are people – the do-it-yourselfers and they want to be able to use some kind of recycled material if possible and then there are those who would rather buy something that is nice and new to work with and build a quite secure food production system. So they’re the two ends of the scale. Then there’s all kinds of alternatives in between.
Ecofilms: Because you’ve got your own favourite method. You are a kit manufacturer. What are your kit systems made from?
Murray Hallam: We manufacture ours from fiberglass. Marine grade fiberglass, because we believe it’s a very durable material and if you’re going to make a food production system then it should be good. Thats what we believe because the most important thing in our daily lives is making sure that we can have food security and most people who come to aquaponics are usually interested in food security and food purity.
These are the two top priorities, so we believe that fiberglass being a very durable material and its also inert – chemically neutral once cured, is an excellent material to use for your tanks and your troughs in aquaponics systems.
But having said that, there is obviously a lot of other materials that you can use that are quite good.
Ecofilms: One of the things that most people don’t concern themselves with is the very fact that aquaponics is not here for a day or a week or a month. You’re going to be running a system that has to produce food for well over six months, a year, three years or five years. We’ve had our system now running non-stop for three years and I can tell you it’s just pumping out an enormous amount of food. But as those years roll by you start worrying and thinking to yourself “Gee, I wonder what’s in the tank that could perhaps leach out and become a health issue?” So I think that it’s something people have to think about when they choose a tank and what’s inside the actual surface of that tank?
Murray Hallam: That is true and that’s why we like fiberglass – marine grade fibreglass so much because we know that it’s a 50 year product. Its infinitely repairable and it is definitely chemically inert whereas a lot of other plastic type products may well leach things into your system. Just think of the fish for example, they’re going to be living in a tank for at least a year and if there’s anything leaching into the tank any nasty little chemicals – minute quantities thereof, then your fish have a whole year to pick that up and absorb it. So theoretically you could be worse off using a low-grade tank and low-grade troughs that may be cheap to buy in the first place but you could be worse off in the end. You are trying to escape from the chemical input into your life by doing aquaponics and you can very easily jump right into a worse end in this situation simply by not getting good quality materials in your setup.
Ecofilms: Murray what about PVC plastic? There are some kit manufacturers that are making them. What’s your view on PVC?
Murray Hallam: I think it’s okay provided you make sure its new and its food safe and it’s not something that is being reclaimed. Generally speaking, the PVC tanks and troughs that are black in colour - now this is not always true, generally speaking, they made from reclaimed plastics and therefore you never entirely sure whats in them. Coloured ones are generally okay provided they are stamped and approved as food safe.
Ecofilms: What about people that immediately go to hardware stores and look for tanks that have another use – say rainwater tanks here in Australia? Whats your view on repurposing rainwater tanks for Aquaponics?
Murray Hallam: Rainwater tanks are quite okay. They are actually quite good here in Australia anyway, they’re made from food safe plastic material and are quite good. Its a good use for a rainwater tank not the cheapest (method) really but it’s it to good use for a rainwater tank to turn it into an Aquaponics system. Lots of people cut them in half, use the bottom half for the fish tank –depending on the size you want to get of course. Its a good way to go.
Ecofilms: And bathtubs? There seems to be a lot of people that go to the local rubbish tip looking for bathtubs. Can you tell us whats your view on bathtubs?
Murray Hallam: Well its a good way to get started. If you’re a person who doesn’t have much money to spend at this particular point when you decide to start in Aquaponics, then putting together a system out of a few bathtubs is not a bad way to go. I wouldn’t want to think it would be a permanent idea but it’s certainly a good way to get started and to just feel how it goes and how it works and to just see if you can do at your place. Most people that we’ve encountered that start down the bath tub route, end up upgrading to something better and that’s not a bad way to go.
Usually old bathtubs, depending on how old they are of course, are enameled. They could be metal with an enamel coating which of course is inert and food safe. There are plastic tubs, some of which are cheap and nasty made of materials that are not food safe and then the better quality fibreglass bathtubs are quite good. Once again, if you’re going to use recycled materials you need to find out what kind of material it is and if you have any doubt do not use it! Simple as that.
Ecofilms: And this brings is down to the minimum size of the tank. In your view offering the best outcome – is there an ideal size in gallons or cubic meters? The dimensions of the tank that will give you the most stability? Is there something along those lines that you’d recommend to an average backyarder who wants to grow food for their family. What sort of minimum or maximum size would you recommend?
Murray Hallam: Look, I’ve seen people build quite successful little tiny aquaponics systems out of a couple of old aquariums and make it work but the more water you have in the system, the more stability you are having in both pH and temperature and that becomes more and more important for your fish that you have pH stability and temperature stability. As much can. So we have found in our part of the world – south-east Queensland that a tank of about 1000 L or 250 gallons of water is a good size because of that size you do have a measure of stability in both those parameters and thats important because if you spend the whole time chasing pH, trying to keep it right and also difficulties with large temperature swings when is a hot day, the temperature of the water goes up – if you got a small volume of water then your water temperature will tend to follow the temperature of the day. Whereas in a much larger volume of water – it takes a lot longer to change that temperature which makes your fish a lot happier and a lot more contented, and your plants too by the way.
Huge temperature swings in the water is not good for your plants. Roots zone temperature can become very important in growing your plants successfully.
Ecofilms: What about those people that want to do it themselves and use concrete? They fill it up with water and then throw fish in. What you say to them?
Murray Hallam: Well they’ll have problems with their pH. Concrete has got a lot of lime in it and even old concrete tanks still have a lime content which will tend to make your system alkaline and we need to have our system at around about 6.5 pH for everything to be ideal. If you have a concrete tank you’ll find very hard to keep it down below seven. Very difficult indeed, so if people want to build larger concrete tank out of something like concrete blocks, then they should be prepared to coat it with something. Some kind of paint that once again is inert and safe for human use, potable water use, but that adds more expense.
Ecofilms: As an alternative you can get stainless steel, copper or zinc tanks. Say someone found one in in a garage sale or auction and they came home with a large copper tank. Would that be suitable?
Murray Hallam: No definitely no copper. Its not good for fish. As we know, they paint the bottoms of boats with copper paints in order to repel fish and crustaceans and barnacles and the like, so it’s not good for our fish to be in a copper tank. Likewise zinc, in fact zinc or galvanized tanks are poisonous to fish. Quite definitely so. Having said that, some of the newer products that we see used in Australia to make metal tanks – one that is called zinc-alum is not so bad because that actually has a very fine plastic coating over it. Then we talk about stainless steel tanks? I’ve seen customers find old milk vats for example from a disused milk factory and stainless steel tanks are really very good actually. If you are going to build one from new then expect to go a visit your bank manager because they are very expensive.
Ecofilms: Now you recently released a DVD called DIY Aquaponics where you make a CHOP2 system from IBC tanks or tote tanks as they call them in America. What about those sort of systems? Are they quite safe?
Murray Hallam: It’s really a good way to go actually for a recycled materials usage, to be able to use those IBC’s or tote tanks. They’re available almost everywhere in the world you’ll find them. Just be careful that you find ones that have not had toxic chemicals in them because obviously agricultural chemicals are transported in them. The tanks if you obtain them from the first user, they will still have a label on them showing what was transported in them. If you get one that’s had some safe material like for example some kind of acid that washes out very easily with water, there are a number of ones we often obtain for customers that have had pool chlorine in them. Tthat’s quite good as it washes out quite well.
Other ones have been used to transport bulk food substances, like orange concentrate, orange fruit juice concentrate on that kind of thing. They’re quite good to use. You’ll need to paint or protect the IBC tank somehow from sunlight because the plastic material that is used will eventually break down with UV light so they are not a long-term option in that regard unless you go to the trouble to make sure that they’re shielded from direct sunlight.
Ecofilms: What about people that they want to use plastic sheeting? They would dig a hole in the backyard and there are going to lay sheeting over it and somehow cover it over stones and so on and make a pond Aquaponics system. What’s your view on plastic sheeting?
Murray Hallam: Well actually its not a bad way to go. Once again provided you buy good-quality plastic pond liner. Or a dam liner. Make sure it is suitable for potable water or human water use. Its not a bad way to go. You can build a container of timber for example or lumbar. Get the shape you want and then line it with the plastic liner. Its not a bad way to go and its reasonably economical as well. On the downside, when you’re putting your media into it, your gravel media into it – you need to be careful not to puncture the lining. If you’re going to keep crustaceans and for example, or some kind of Yabby or claw-fish, they might tend to bite holes in it which is not good, but for ordinary fish like Jade Perch or Silver Perch, Tilapia, those kind of finfish, it works really quite well.
Ecofilms: I wonder what sort of life you’d expect to get out of a pond liner?
Murray Hallam: Well the sun is a marvelous thing. It will break anything down eventually. I would once again wanted to be protected from direct sunlight and make sure that it is housed in a good greenhouse or the like. Most of those pond liners that I have seen have got an estimated life of about 10 years. That’s provided their protected in the appropriate manner and they don’t become punctured or in any way compromised like that. But it’s not a bad way to go. We’ve seen commercial systems. We were in America recently visiting some different farms and we found that they had made their troughs out of timber or lumber and lined them with the plastic liner that we’ve just described. It works quite well
Ecofilms: So you’d recommend if you’re building a small-scale commercial floating raft system you’d recommend that you did it in timber and plastic liner?
Murray Hallam: Its certainly one way to do it. That’s for sure. It’s quite able to be done by people with moderate skills. Its not a high skill thing and so it can be done by ordinary people quite well.