System Layout #2 – The microFish Farm

The microFish Farm is a small recirculating aquaculture system (with a capacity of 600 to 1200 litres) characterised by a square fish tank and an overhead bio-filter.

The microFish Farm

It earns its place in our list of system layouts because it has been replicated many hundreds of times throughout Australia.

When we first developed the microFish Farm concept, several years ago, it was innovative for a number of reasons including:

  • It was the first turnkey backyard-scale aquaponics system in Australia.
  • It featured vertical stacking of components.  The bio-filters were located on top of the tank which avoided the need for a support frame.
  • Its compact footprint and efficient use of space.
  • Its ability to be used inside or outside.  In its second incarnation, it featured a long rectangular bio-filter that could also be used as a grow bed.
  • It demonstrated that useful quantities of freshwater fish could be grown in as little as 600 litres of water.
  • Its use of an access barrier – to keep toddlers, sunlight and predators out…..and the fish in.
  • Its simplicity.
  • Its capacity to be used in conjunction with a wide range of hydroponic and soil-based growing systems.
  • Its ability to be disconnected from the growing system in the event of disease or infestation in fish or plants……or to minimise overnight heat loss.

Square tanks offer efficient use of space

A small submersible pump raises the water from the fish tank to an overhead flood and drain bio-filter.  When the water level reaches a certain point an autosyphon is triggered unleashing a torrent of water back into the fish tank.

Our first microFish Farms were built from off-the-shelf components.  We used 780 litre HDPE plastic bins (made for the horticulture industry to transport fruit and vegetables) as fish tanks.  Recycled plastic barrels or stacking plastic crates (filled with oyster shells) were used for trickling bio-filters.

Fibreglass variants of the microFish Farm are also offered by two Australian manufacturers.

The fibreglass variant of the microFish Farm

Where the movement of  water through the overhead bio-filter is controlled by an auto-syphon there will be modest fluctation in the fish tank water level.

The microFish Farm can also be set up for continuous flow.  Under this regime, the water level in the fish tank does not fluctuate.

Another innovative feature of this little unit is its ability to function as a stand-alone recirculating aquaculture system.  As such, it can be housed in a shed.

If located outside, the overhead bio-filter can be planted out with seedlings, at which point the microFish Farm becomes a small aquaponics system.

A variety of other hydroponic growing systems can be added to the system – or the water from the fish tank can be used to irrigate soil-based food gardens.

Our 4 Tank system comprised (not surprisingly) four microFish Farms alongside of each other and provided the opportunity to trial different species and age groups.

The 4 Tank System - clean fresh food just eight feet from our back door.

While it suffers from some of the same limitations as other conventional aquaponics systems, the microFish Farm is both innovative and versatile.

Well managed, it is capable of producing plenty of clean fresh food.



  1. Paul V says


    What about these? 2005… and I am certain it was being done well before these. I will go so far to say, it was being done before digital cameras and the internet. I know because I was doing it with the same nally bins pictured below 5 years before.

    That was growing these…

    • says

      Paul V………given that variants of the microFish Farm have sold in the hundreds, the claim to being the first turnkey backyard aquaculture/aquaponics system in Australia is probably sustainable, however, in deference to your evidence, I’ll remove the word aquaculture.

  2. Paul V says

    Sorry had to wiki “turnkey”

    A turn-key or a turn-key project is a type of project that is constructed by a developer and sold or turned over to a buyer in a ready-to-use condition.

    I was not aware anyone was selling systems like these. You do know that it was an aquaponics system in those photos?

    Anyways, each to their own. I lay no claim to being the first. I simply think it is a big ask to believe that you were.

    • says

      Paul V…….the fibreglass variant of the microFish Farm was originally designed for sale to schools.

      That arrangement was breached by the maker who then “adopted” the design and offered it for general sale. Since it was first developed, the microFish farm (and various other identical products by other names) has sold in the hundreds.

      It came as a ready-to-use kit and, as such, it fits the definition of turnkey.

      In fact, if we look at the wording of the original claim, and your photos, I’m inclined to reclaim the aquaculture part, too.

      Of course, if anyone can present evidence (photos and verifiable data) that refutes this claim, I’m happy to defer.

    • says

      Paul V…..thank you for your commitment to ensuring the accuracy of our claims. It looks like we’re back to “It was the first turnkey backyard-scale aquaponics system in Australia.”

  3. Paul V says

    Fair enough Gary, I will leave you to your claim.

    I am interested to know what “useful quantities of freshwater fish” actually is. I mean from a back yard point of view, for say a family of four. What sort of weight of fish can be successfully grown in these aquaponic systems and in what sort of time frame?

    I get a little confused as the chap that “adopted” claims it is best to have a 1:1 ratio volume growbed to fish tank. How does that work out with your set up?

    • says

      Paul V…………thank you Paul…..very gracious of you.

      I grew over 20kg of jade perch in my first mega bin system in 36 weeks……so any well-managed microFish Farm of a similar size should be able to do the same thing. I think it’s important to point out that jade perch are quite tolerant of indifferent water conditions. My experience of murray cod and barramundi suggest that the stocking rate would need to be lower – perhaps half of that of jade perch.

      Of course, we also harvested many kilos of vegetables, too.

      A standard microFish Farm (fish tank and bio-filter) is much less than 1:1 (more in the order of 1 litre of bio-filter to each 4 litres of fish tank volume). I found that these little systems worked best if the overhead bio-filter was not used to grow plants and if some effort was made to remove solid wastes (we used orphan socks and filter foam).

      When the system was not hooked up to other hydroponics growing systems, we used the water from it to irrigate our square foot and raised bed gardens. This had the effect of water replacement while still being water-wise. Water efficiency was leveraged further by the fact that we only use rainwater in our AP systems.

      At the end of the day, the microFish Farm suffers from the same limitations that any conventional aquaponics system does. In the absence of mechanical filtration, it relies on good management to produce much of anything at all.

      As we’ve discussed in other posts, it’s overdue for more design work. I’d be delighted to be able to grow a redclaw harvest like the one in one of your forum photos.

  4. Paul V says

    20kg of Jadies in 600 liters of water (33kg/m3) is quite an accomplishment! Well done. Knowing a little about Jade Perch and their culture in RAS systems, just to clarify, this 20kg in 36 weeks is 20kg of what size fish (350, 500grams etc)?

  5. Midion says

    Yea, I would also like to know that. I’m getting into aquaponics and want to raise as much you can in 600liters of water in 36 months. I have others that can’t but I really would like to know. Did they start off as fingerlings?


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