C.H.O.P Aquaponics Operating System.

CHOP System.

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 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.

Happy Aquaponics.



The Four Hard Questions For Commercial Aquaponics.


Aquaponics Course

A student from Egypt receives his Certificate on completion of the February 2014 Practical Aquaponics Commercial and Small Farm course.

I have been most fortunate over the last few years in that I have travelled widely around the world and visited and consulted on many Aquaponics farms.  It is always on my mind to identify and clarify the most common reasons some farm projects succeed and some fail.   There is a multitude of reasons both ways, but here I am attempting to condense it down to the four most obvious.There are many many successful farms. For the most part they are quietly going about their business, doing business, expanding business and making money.  Bad news travels fast so it is not surprising that we hear the failure stories.   Almost all Aquaponics farms I have been involved in have either failed or succeeded based on how well or otherwise they have dealt with these four issues.

There is nothing wrong or inherently bad about growing top quality produce. In fact, it is a business activity for this time, without doubt. We see everywhere an increasing demand for quality pure food.  People from all socioeconomic groups are seeking better food for their families.  I should not need to spell out all the bad things that are happening in our “normal” food supply chain. Instead we can concentrate in delivering the “good news” about Aquaponics;  nutrient dense, clean, tasty food.  People everywhere get excited about the possibilities Aquaponics offers, from a commercial business perspective and as a consumer.

It really is a “no brainer”. Good, pure, high nutrient density produce will sell for premium prices.

Aquaponics produce is a great product to sell and should be relatively easy to market in most parts of the world.

Many see the beauty and the opportunity Aquaponics offers and set out to create a business plan, a construction plan to “Go Commercial”.

The four big questions you must ask yourself and your business partner if planning to “Go Commercial” are:

Q1. Will I have a viable and vibrant Marketing strategy?
This is the most important aspect of any business and Aquaponics is no different. The old adage “Build a better mousetrap, and the world will beat a path to your door” is just not true, unfortunately. You will need to be very intentional in researching your particular location, identifying just who the clients are, then getting your message to them.   And this task will NEVER end.  It is not a “set and forget” type of thing.

Q2. Do I have enough capital?
Make sure your set up costs and earning projections are realistic.  Remember Murphy’s law? “Anything that can go wrong will go wrong.” Any form of farming is a risky business. Make sure you have enough cash to see your project into profit. Go over your cost projections over and over again. Be very conservative in your numbers.  Ignore the crazy claims made by some - “1100 vegetables and 400 pounds of fish per year” from a system about the size of a snooker table, and tens of thousands of pounds from something as big as a family tennis court.  Growing produce by the Aquaponic method is not some “dark art” that will produce magical harvests and truckloads of money.  Gather information from a reliable source, or two.

Q3. Do I have a good work ethic?
This may sound like a silly question, but many an “investor” type person’s idea of running a farm is sitting all day in an air-conditioned office and expecting the “hired hands” to get it all done.  If you are going to be a successful farmer then you need to be a farmer. That means getting out there at daylight, harvesting the produce and getting it to your clients.  I have seen a couple of farm failures that have flopped for this very reason. The guy turns up at 10 am and is gone again by twelve.  Farming is farming.  Having said that, one very experienced and successful farmer says that Aquaponics farming is the easiest farming he has ever done, but it is still farming.

Q4. Do I have unrealistic expectations and have I set unrealistic pre conditions?
Some contact me and ask for advices and then place unrealistic conditions on their proposed project. The most common one I see of late is: “I expect to be introduced to a half-dozen successful farms and I demand that these farms reveal their last two years profit and loss statements and that the farm only has one revenue stream”.   This attitude reveals an underlying desire to just copy someone else’s plan and be guaranteed success. If this was actually done it would almost guarantee failure.  Someone else’s plan can never be your plan.  Their marketing strategy can never be a perfect fit for your location. Their work ethic is most likely very different from your work ethic. Their capital availability is very likely to be different from yours and so on it goes.  It is just plain silly to demand such things.  People that are successful farmers are not very likely to open their books to any old Tom, Dick or Harry that demands to take a look.  You need to be first convinced that Aquaponics produce is a good and saleable product, then you need to have a plan to sell it for the highest possible price.  Having said that, it is good and worthwhile to be able to view some case studies. No one makes money from growing produce, money is made from selling the produce.

Never discount other revenue streams from your Aquaponics farm plan. Businesses everywhere and of every type strive to create and identify as many revenue streams as possible to incorporate into their business plan.  In my view it is a recipe for failure to place such revenue restrictions on your Aquaponics business model.   We see this idea of revenue only from one source being sprouted on forums and email groups, interestingly from people that do not even have a Aquaponics farm or, in some cases have not even had a small Aquaponics home system.  Most promoting these fanciful ideas have never even had and run their own business; of any type.

In creating your business plan it is prudent to be assured that you can ultimately make it pay from the core activity alone.  However, do not discount or exclude other possible revenue streams.   Other revenue streams are very useful in providing cash flow, especially during the development and bedding down phases of the business plan implementation. Every business has seasonal or circumstantial dips in revenue from the core activity. That is when the other smaller revenue stream activities carry the business through those down times.

So, the questions you need to answer very truthfully to yourself are:

1       Will I give due attention to my marketing plan?

2       Will I have enough cash to see the project through to profit?

3       Will I work like a farmer and do on a daily basis the work that needs to be done? and

4       Do I have very realistic expectations?

Murray Hallam's Practical Aquaponics.

Truly excellent Commercial and Small Farm training delivered by Murray Hallam himself.  Find out how you can attend one of these 4 day or 1 day Aquaponics courses HERE.

Murray Hallams Practical Aquaponics - Aquaponics based on practical experience.

Mod #2 A Second Pump Fitted to Your CHOP Mark2 System.

A second pump built into your CHOP Mark 2 operating system to provide redundancy.   It may seem to be a contradiction to add a second pump to a CHOP system but it is not such a bad idea.  Pumps are a mechanical devices and therefore are subject to failure. Even the most expensive pump will give out one day. Obviously we will fit the best pump we can afford to our CHOP system, and being prepared with an additional pump at the ready is a good idea.

It is very upsetting if you have a pump failure and there is no readily available replacement.  With no water movement and exchange the fish tank will quickly become polluted and fish deaths will soon follow.  Pumps have a uncanny ability to fail in the middle of the night, at weekends or when you are away.

Two pump layout. Only one pump needs to be operated at a time.

Two pump layout. Only one pump needs to be operated at a time.

Fit a second pump to provide water security for your CHOP Mark 2 system.

At the very least, have a replacement pump on the shelf at home complete with fittings to allow you to make a rapid change if it becomes necessary. Have the joining system already attached so that rapid changes can be made

Left: Snap-on Fittings  Right:  Barrel Union,  Murray Hallam Aquaponics.

Left: Snap-on Fittings Right: Barrel Union,

Left:- Snap on fitting. Right:- Barrel Union. Examples of ways to quick connect and disconnect your spare pump.

Another way is to have the second pump actually plumbed into the system ready to go at the flick of the switch.  I run two pumps on each of my two bigger systems I have running. The Quad kit and the Homestead kit. I am gradually moving through all my other systems and fitting a second pump to each.

Option 1.
Each pump is fitted with it’s own independent pipe system leading from the sump to the fish tank or grow beds,  in waiting ready to work in an instant.  If pump “A” fails or needs maintence down time, pump “B” is brought on-line. Have both pumps sized (capacity) so that each pump is able to run the system by itself. A little over capacity is not a bad thing in this case.   Additional expense in pipe work is the downside to this plan and if the operating pump fails for any reason, there is no automatic switch over to pump”B”.

Option 2.
Run both pumps in parallel.  This is my preferred option. It is easy to set up and is worry free.  Have both pumps sized so that one by itself will just run the system but has no over capacity.  Having the pumps sized down a little will save on energy costs while giving the system safety you desire.  A bit like a single engine or twin engine aircraft.

Here is how to connect the plumbing so that both pumps can be hooked up ready to go.  I am showing two alternative pipe layouts for your consideration.

See as per the drawing.  Each pumps is run via a pipe through a “Non Return Valve” then the two pumps output pipes meet at a “T” joiner to bring both pump outputs into the one line where the water is then run to the grow beds and fish tank.
If one pump fails the other pump will carry the load.  The water will be prevented from flowing back through the failed pump by the non return valve.

Alternatively, one pump can be run directly to the fish tank and one to the Grow Beds with a balancing pipe between.

Alternate Layout for pump arrangement.

Pump and Pipe Layout "B". This layout will deliver more water to the fish tank and grow beds than layout "A" This is because we are using two pipes instead of one to deliver the water. If one pump fails the water from the operating pump travels by the balancing pipe to the other line and is prevented from back flowing into the sump by the non return valve.

It is important to have both pumps of the same capacity model and brand.  If one pump has more capacity than the other it will do all the work and the other will be “lazy”  It is also important to have correct sized pipe to carry the volume of water easily.   Too small pipe diameter will cause reduced flow and loss of pump performance.

This arrangement works well with any style of system layout.  If you are not running CHOP or CHOP Mark 2 this pump arrangement will work well for you eliminating one possible failure point in your Aquaponics system.

CHOP Mark2

Happy Aquaponics
Murray Hallam at Practical Aquaponics.

Aquaponics CHOP Mark 2 Operating System.

CHOP or Constant Height One Pump has been adapted by Aquaponics enthusiasts around the world now for the last few years since we coined the term.  The other variant Chift Pist runs in a similar way.  I noticed a problem with water levels whilst working on a small commercial CHOP system we were commissioning just over a year ago.  We needed to refine the process for our client,  so we came up with a solution that we’ve been trialling now for over a year.


It runs so beautifully. I’m very excited by it.

I am so certain this is a better way to run your aquaponics system that we have adopted CHOP2 into all our new larger Aquaponics kits that we design and build.

So what is CHOP Mark2 and why should you consider using it?

Operating the old CHOP method water is pumped up from the sump to the fish tank and from the fish tank runs back to the grow bed and sump by gravity. This system works very well but it requires that the grow beds be perfectly level to function properly. With CHOP Mark2 there are a number of advantages you can study if you watch and play the accompanying animation.

See Animation HERE

With CHOP2 you will notice that the pump sends the water to the grow bed as well as the main fish tank simultaneously. The water from the fish tank and grow beds runs back to the central sump.

It’s kind of like a double loop water flow with the sump as the central mixing point. It works extremely well.

So what are the advantages of modifying your system to CHOP Mark2?

The main point is that grow beds do not need to be perfectly level to function properly.  A crucial point if you are running a number of them on uneven ground and have encountered problems with your auto siphons. Because each grow bed has an independent ball valve, the water flow can be regulated with greater control than gravity fed flow under the old CHOP system.
Recently we commissioned an 18 bed system utilising two of our large commercial fish tanks.  To facilitate good water flow we used CHOP Mark2 together with sequencing valves.

Because each Fish Tank also now has its own ball valve it means water flow to the fish tank/s can now also be regulated as well.

If you need to harvest your fish and control the water depth or do any maintenance at all, you now have complete control to stop water flowing to your main fish tank or even drain it,  but not stop the flow to your other grow beds.

More control for the aquaponics enthusiast also means more control over winter temperatures as the mercury plummets.

In colder climes operators can turn off their grow beds at night but still have their main fish tank running as normal.  This is a great boost for owners who complained that their grow beds were acting as a heat sink at night, plunging their water temperature down a number of degrees.

A side benefit for users who will modify their system to CHOP Mark2 is that should they decide to change their system from a gravel based media to floating raft, CHOP Mark2 will accommodate their design shift.

If a combination media and raft system were to be built,  Swirl filters or regular filters can be fitted easily into the fish tank to raft section, then we can allow the rafts to drain back to the sump.

An elegant solution.

But what are the disadvantages of running this system?

The critics will say that the sump pumps half the water back to the fish tank. Surely this can’t be good for the fish, as solids are returned back to the main tank?

Logically this may seem to be the case, but over a year of trialling this system with hundreds of fish we have discovered that the sump itself acts as a settling tank for solids, something that we didn’t expect to see and something that has never happened under the old CHOP system.

You will need to clean your sump occasionally as the solids will be noticeable around the sides of the sump.  This is a good thing and it is not hard to do.

What about fish nutrients?  Aren’t you halving the number of fish nutrients by returning the flow back to the main fish tank?

Some may think that the nutrients from the fish tank will be diluted as the sump water is pumped partly back to the fish tank and partly to the grow beds.  In just over 12 months of running we see no reduction in nutrient to the grow beds.
Conversely,  some may think that the nutrient level may be too high and perhaps there will not be enough filtration or bacterial action because some of the water that has just arrived in the sump from the fish tank will be returned directly back to the fish tank.

We initially felt some of these fears ourselves, but with 12 solid months of field trials behind we see the systems running exceptionally well.

We see CHOP2 as a definite improvement for the Aquaponics community around the world.  Come back in 12 months time as see how many users have modified their system to CHOP Mark2.
People always vote with their feet. They know when they’re onto a good thing.

The next generation of CHOP.   CHOP Mark2

1  Grow beds do not have to be exactly level with each other as they do for CHOP mark 1
2  Flow to the grow beds can more easily be regulated than with a gravity flow.
3  Fish tank can easily be isolated if required for whatever reason.  We regularly switch off the fish tank to pump it down to do a fish count or capture and the grow beds are still left running.
4  Grow beds can easily be isolated if winter night time shut down of the flow to the grow beds is required while fish tank still enjoys excellent water exchange.
5  If a combination media and raft system were to be built, swirl filters or regular filters can be fitted easily into the fish tank to raft section then rafts drain back to the sump.

Happy Aquaponics
First Posted on October 27, 2010

Aquaponics Chop 2 Powers on – 18 Months Later.

CHOP 2 Aquaponics Operating system

CHOP 2 Aquaponics Operating system

How quickly does time fly? Since building and testing his innovative toteponics system based on CHOP2 technology we caught up with Aquaponics guru Murray Hallam to ask how its all been going? Murray immediately lights up with his usual enthusiasm, “Can you believe it – its 18 months since we built that first system and its still functioning perfectly well, day in day out.”

The DIY Aquaponics DVD that features how to build this system in detail has also been tremendously successful with aquaponics enthusiasts right around the world enjoying Murray’s laconic style of instruction. So successful that Murray has started building kits for those people who want to buy a CHOP2 system pre-built with all the fittings ready assembled.
You can buy the fitting directly from his website in Australia or from Sylvia Bernstein’s Aquaponics website in the US which has American plumbing parts that are slightly different from the Australian fittings. But both fittings will work just the same.

Murray Hallam in front of his more recent CHOP 2 System

Murray Hallam in front of his more recent CHOP 2 System

“We’re selling around three IBC CHOP2 kits a week, going out our door here in Australia!” says Murray.

Murray has a two to four months back order for his quality line of aquaponics system built from fibreglass. Murray says Australians love building and tinkering on weekends with Aquaponics. “Most people with a little handyman skills like to assemble it themselves,” says Murray, but there are others who want everything delivered.

“We cater for everyone.” he says.

“The only thing if you buy our IBC CHOP2 system that you will need to source yourself are the concrete blocks and timber sleepers to hold the tanks in place. These things can be found in any hardware store.” he said.
But are there any problems with assembling the kits? Murray says most people that ring him usually have difficulty locating the pdf instructions that come on the DVD. “We usually explain where to find it and what software they need to view the file on their computer.” he says. “But the response has been great.” Murray says he continually gets fan mail and thank you emails in his inbox.

“If people follow the instructions they will build themselves a quality Aquaponics system.” said Murray. “But they have to follow the instructions. All the measurements and parts needed are on the disk.”
“And if they don’t want to build it they can buy just the parts they require from me.” he said.

Murray clowning around with "Gary" his talking fish!

Murray clowning around with "Gary" his talking fish!

Murray has recently created a special CHOP2 Toteponics forum on his website where owners of these systems can upload photos of their systems, shoot the breeze and ask questions. “I gives people tremendous confidence to see their own system producing great vegetables and fish at home.”

When Murray Hallam launched CHOP2 he wasn’t alone from some critics who said his design was flawed because he recirculated the water in the system in an unusual way. “Some people said that the fish would go blind!” laughed Murray, “It’s a total furphy because some of the suspended solids get returned to the fish tank!”

But all the solids are eventually filtered through the growbeds as normal and 18 months later the fish have been harvested and the vegetables replanted.

“We currently have lettuce, asian greens, a mustard bush, tomatoes and an aloe vera plant transplanted from one of my other systems.” he said.

Being an innovator Murray has begun testing the juice from black soldier fly larvae as a source of nutrient for aquaponics. “I’m using it in the same way you would add worm-juice to a system.” He adds. “I want to see how well it performs.”

So are there any secrets under wraps that we can divulge to our readers? Murray teases us with his mischievous grin. “I got a new Aquaponics system design based on CHOP2 – and its a little beauty, but I can’t say anymore!”

Like a lot of Murray’s inventions – he wont release any more information until he knows it works.

Clontarf High Does 12 Months On Aquaponics.

Clontarf High has completed the first 12 months operation of its FloMedia Aquaponics System.  The system is based on CHOP 2 making use of auto siphons to provide the ebb and flow action that is so important for good aeration in Aquaponics systems.

Clontarf High Aquaponics Educational system under construction December 2010

Clontarf High Aquaponics Educational system under construction December 2010

The install consists of 3 x 1250 ltr windowed fish tanks and 4 x media beds together with 2 x floating raft beds.

The system combines to work extremely well. The three windowed fish tanks provide excellent viewing allowing the students to conduct their science projects with ease.  Having three tanks allows for three different species of fish to be kept.   The water flow provides for excellent filtration and nutrient delivery to the media and raft beds.

Aquaponic Raft beds ready for planting.

Marine Coordinator Adam Richmond says the Aquaponics system has been a hit with the students.  "There is so much science we can teach out of Aquaponics "says Adam.   "The variety and scope of subject matter that can be taught is expanding each month, it is a very exciting teaching tool"

Aquaponic windowed fish tank

Windowed fish tank with Jade Perch and one Cat Fish.

                      The FloMedia system combines both Media and raft systems into one dynamic Aquaponics unit.

FloMedia Aquaponics systems.

          Murray Hallam's Practical Aquaponics.