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5 Great Fish options for your Backyard Aquaponics System

May 19, 2014 | Aquaponics | 27 comments | Author:


Setting up a good little backyard aquaponics system can ensure you’re dripping with herbs and greens on a regular basis, with the addition of an occasional home-grown fish night!

But which fish? Not all are suitable, but there’s a few key species that are especially excellent for home aquaponics setups… 

cafe aquaponics system
A simple, no-fuss backyard cafe aquaponics system, just after it’s construction – this one contains herbs for the kitchen, and goldfish to keep the nutrients going around

There’s a lot to be said about the beauty and abundance of aquaponics systems. And indeed we’ve said it a couple of times, because we definitely believe it to be a truly efficient example of a nutrient recycling system for growing food.

Aquaponics in its most basic sense is a combination of aquaculture and hydroponics.

The use of these two systems together – which on their own can have some negatives – allow for a close-loop (ie not entirely closed, but pretty close) where the waste from the fish supply nutrients to the plants, which in turn filter and clean the water to be return to the fish tanks.

Essentially the negatives of each system are turned into superb positives!

Having an aquaponics system set up – no matter the scale – can put a turbo booster into your herbs, vegies and leafy greens growth, and in the meantime there’s the opportunity to potentially grow your own fresh fish at home.

There’s an abundance of ways you can set up your own systems, and there’s also quite a few fish species that integrate well into these.

We grabbed a cuppa with our clever teacher Floyd Constable, who has built all manner and size of systems in the past, to quiz him on his five favourite fish for backyard-scale aquaponics…

silver perch

1. Silver Perch

These fish are good eating and are easy to manage and grow. They have a wide environmental tolerance range, and can handle cooler water – however their growth will slow.

Avoid using them where it can get very cold for extended periods, as their metabolism slows right down and they wont grow or produce high amounts of nutrients for your plants.

They have a largely vegetarian diet so growing most of their food is possible.


2. Trout

Trout are very fast growing (6 months or so) so are exciting to watch progress and are a great food conversion ratio and very good eating.

They’ll jump out of the tank so you need a lid or cover on your set-up. They can’t handle warm water, it needs to be kept really cold, so are most suitable for very cold regions.

As they’re a carnivore they need commercial pellets for food (or a home-made equivalent), and can have cannibalistic tendencies, eating both their own and other species of fish.


3. Barramundi

Very similar to trout but rather than requiring only cold water, barramundi really need consistent warm water.

Due to these requirements, and depending on their climate, some people will choose to grow trout through the winter and barramundi through summer.

They are also fast growing and good eating, and likewise will jump out of their tank and cannibalise each other. Generally larger fish will eat the smaller fish so this can be managed by grading the fish between tanks depending on size.


4. Tilapia

These are the perfect all-rounders for aquaponics. They grow fast, breed in the tank and taste good for eating. Being mostly vegetarian you can grow your own fish food for them.

They handle a wide range of tank conditions from temperature, pH, nutrient and oxygen levels and more. They’re interesting to watch in the tank due to their breeding.

Perfect in the tropics and subtropics, they can also suit temperate climates, and are the most commonly used fish in aquaponic systems around the world

**Throughout Australia (except WA) tilapia are banned due to their ability to overtake local waterways. Darnit.

goldfish in aquaponics system

5. Goldfish

Not all who set up a backyard aquaponics system have a great deal of space, or are necessarily keen on eating the fish. In these situations goldfish are great.

They’re easy, cheap, resilient, tolerate wide and fluctuating conditions, and are beautiful to look at and incorporate into your garden.

You can grow a lot of your own food for them and they’re useful in just about all environmental conditions – that said, they don’t like it super hot though.

And of course – don’t use goldfish anywhere there’s the chance they can escape into natural water systems.

What fish have you had success with? We’d love to hear…

aquaponics course milkwood

We’ve got a Backyard Aquaponics course coming up next month in Sydney…

All our aquaponics articles + resources are here…

Fish images via flickr’s creative commons: silver perch, trout, tilapia, barramundi

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  • swo8 May 19, 2014 at 6:14 am | Reply

    How do you know that the tomato plants you buy aren’t GMO’s?

  • Kirsten May 19, 2014 at 7:10 am | Reply

    Well, fortunately, GMO’s have very limited reach in Australia thus far, and don’t extend to veggies like tomatoes.

  • max May 19, 2014 at 7:16 am | Reply

    About the fish..
    I would love to talk to somebody who does Trout in winter and barra in Summer – anybody north of Brisbane or with a similar climate. I’m at Crystal Waters.
    Tilapia and Goldfish are not legal here and we have plenty of perch but they do not appeal to me.
    I’m surprised that Catfish got no mention?
    Where are people getting fingerlings from? They seem far too expensive here.


    1. Bits Out the Back.. May 19, 2014 at 8:00 am | Reply

      I got 50 each of the Jades & Slivers from SEQ Fish the other day Max for $1.50 which I thought was reasonable.. They have a good selection there.. Have been told that folks have tried & succeeded with trout up here (we’re in Ipswich) but you need to be on the ball with them as we have such a short growing season climate wise.. Have to buy them in as “Ornamentals” from the southern states as well I think ;)

      1. max May 20, 2014 at 8:22 am | Reply

        I checked and $ 1.50 is not a bad price. We have heaps of Silver in our large dams and even after flushing them I don’t find them very attractive . Never had Jade but they too sound fatty.
        A combination of Trout and Bara could be ideal but I sense that we are a bit warm for Trout and a bit cool for Bara.
        We have a long boundary with the upper Mary and it runs clear most of the year and the Catfish are excellent eating. maybe I should not bother with stocking fish?

      2. Neil Willmann May 20, 2014 at 11:03 am | Reply

        I wish there was an easy way to lower the water temps for raising cool water species. Why not incorporate a solar collector or composting pile as a free heat source for warmer species in your area?

  • Alacoque May 19, 2014 at 9:17 am | Reply

    We have a little pond/water feature with (I think) zebra fish. They are very happy and keep reproducing and we’ve noticed when we water the pot plants with the pond water they really flourish. We’re thinking of setting up a little acquaponics system using this pond as we don’t really have any more room for larger fish and we live so close to the fish markets anyway. We would set up the veggie beds on the adjacent wall making it a vertical garden. Still in the design stages but nice to see some other fish to consider!

    1. Jenny May 19, 2014 at 10:46 am | Reply

      Hi Alacoque,
      I have a small yard and would like to set up a pond with edible plants and fish. I have heard Zebra fish would work.
      Do you have a photo of your pond?

      1. Alacoque May 20, 2014 at 11:26 am | Reply

        I’m not sure how I could share a photo but it’s a brick pond/water feature, against the wall of our outdoor loo. It’s about 110cm long x 45cm wide x 60cm deep. We have a little pump with a filter that powers an attractive ‘tap’ above off the wall and plants including a water lily, dwarf papyrus, and lots of duckweed!

  • Maria May 19, 2014 at 9:48 am | Reply

    I’d like to play around with this, and am especially interested in the perch. What kind of temperatures slow their growth?

  • davestewart3 May 19, 2014 at 3:43 pm | Reply

    Reblogged this on Slow Natural Living and commented:
    Backyard Aquaponics System

  • Daniel May 19, 2014 at 6:58 pm | Reply

    I am doing an aquaponics project in Kenya and we are trying catfish!

  • duriteaquaponics May 19, 2014 at 11:20 pm | Reply

    Reblogged this on DuRite Aquaponics.

  • Neil Willmann May 20, 2014 at 10:53 am | Reply

    Catfish can also have chickens raised above and they will feed form the droppings. This is often done without the hydroponic plants (called ‘integrated aquaculture’) however in an aquaponics system the water quality is greatly improved for the fish and, of course, there is added integration.

    1. Kirsten May 20, 2014 at 11:02 am | Reply

      Good ol’ catfish.

  • merindakavich May 20, 2014 at 10:57 am | Reply

    re your search for samphire… I used to find it on the shores of Smiths Lake (south of Foster).

    1. Kirsten May 20, 2014 at 11:03 am | Reply

      Thanks! Still searching the estuaries down here. Wrong time of year of course, but I’m still looking ;)

  • Neil Willmann May 20, 2014 at 11:10 am | Reply

    Besides goldfish, there are other things that also work well for aquaponics systems when there is no desire for consuming the fish. One that may not immediately come to mind is turtles. They still produce the needed ammonia (hence nitrate) however don’t demand oxygen form the water. So, consider a turtleponics system too.

  • Fiona May 20, 2014 at 1:04 pm | Reply

    Any thoughts on crayfish or other crustaceans?

    1. Kirsten May 20, 2014 at 4:35 pm | Reply

      Yabbies are great for AQP systems! They do tend to crawl out though, if they can :)

    2. Neil Willmann May 20, 2014 at 4:59 pm | Reply

      Invertebrates in general are more sensitive to poor water quality and this becomes one concern as coupled aquaponics systems can go out of balance. This would not affect hardy fish but crawfish especially in larger numbers might easily be affected. They will have unique requirements e.g. need for hiding places during the molting phase and these would be discussed in aquaculture books for any particular species. There is an Australian book about small-scale blue crawfish aquaculture that would be excellent in designing a crawfish aquaponics system.

  • Daniel Sousa May 21, 2014 at 6:48 pm | Reply

    Reblogged this on Jardins da Hérnia que me Bifurca.

  • Sustainable Impact May 22, 2014 at 9:55 am | Reply

    Reblogged this on Sustainable Impact.

  • […] You might also want to check out fish options at […]

  • cbconserv June 19, 2014 at 1:25 pm | Reply

    Reblogged this on adapt flee or perish and commented:
    Aquaponics show great promise for a climate like Sacramento, where lack of summer rains makes urban gardening without an irrigation source a real challenge – most California farming is done with irrigation, so the closed loop, recirculating system like aquaponics means you save the water that you get in the winter for use year round. I haven’t tried this yet, but i am seriously considering the water balance inherent in such a system.

  • Aqua July 15, 2014 at 4:35 pm | Reply

    Has anyone tried eels ?

  • martin December 12, 2014 at 12:33 am | Reply

    How about using Koi ? anyone got experience with these fish


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