Backyard Aquaponics
A place to discuss aquaponics

Hi, I am doing my research to set up a aquaponics system that will hopefully provide us with some fish and maybe some veg. I really like the idea of strawberries as my daughter loves them and I think it would be real nice if she could benefit from this whole project too. I kept fish as a child and that is probably where most of my motivation for this project lies.

I plan on a setup with two IBC's as my fish tanks, hoping to rear some trout and some tilapia (I know the tilapia will only be in the warmer months until it proves worthwhile to clear out the shed and move the fish into there where I can keep them warm through winter). I was thinking of cutting a 210L plastic drum to give me two grow beds, and then a strawberry tower. Does anyone have some advice/pointers for me, and my main question at this point is for simplicity can I have water running through the strawberry tower all the time or is this bad (please forgive my ignorance)?

Hi soulchyld, I'm also from UK, yeah strawberry towers are supposed to have a constant trickle of water running over the roots.

I would advise against attempting to raise both tilapia and trout at the same time. As you already know they have VERY different temp requirements. You would need 2 separate systems, and in the summer you will still be struggling to keep tilapia tank warm enough, and very possibly struggling at the same time to keep the trout tank cold enough. In the winter the trout will be fine but tilapia will not survive, nor in a shed unless it is heated. The summer months in the UK will not be long enough to raise tilapia to a decent eating size.

But perch, aka redfin to the aussies here on the forum, are native to the UK, and are more tolerant to water quality and warmer temps than trout, they are very good eating, probably better than tilapia, and should be easily available. They don't grow as fast as trout, but should be easier to raise... that would be my recommendation as to choice of fish! If you feel ambitious then do trout, but don't do tilapia unless you are going to install a seriously well insulated heated greenhouse and supplement with electric lighting in the winter!

Good luck and welcome to the forum, there is a wealth of knowledgeable people here, all happy to help you along the exciting journey!

Welcome to the world of aquaponics soulchyld.

Danny's advice on fish species sounds good to me.

Just a comment on your proposed setup. Sounds like you plan to have nearly 2000 L of fish tank volume and only about 160 L of wet media in your growbeds. Unless you plan to have heaps of strawberry towers or extra filtration, it might be worth having a look at this currently running thread viewtopic.php?f=14&t=29185

Good luck and have fun.

Hi guys and thanks for your advice, looks like there will be no tilapia going into my system then. I do plan on filtration, as I don't have much space to have more grow beds, (areas with enough sunlight and space for the little one to play have left me wanting lol). I will have a look at perch certainly, from my understanding of your advice its ambitious to have both species (in separate tanks, same system) but perch and trout is possible?
As far as filters go, I am thinking of having a swirl filter using a 20l bucket maybe with a sponge and filled with oyster shells that feeds into a 210l plastic drum that acts as a sump and bio filter, haven't quite decided on media there yet. The issue I have spotted there with this plan is, as I plan on two tanks, I think its best to have my pump pump out of one tank instead of the sump, to ensure I dont drain this tank in the event of an accident install a float switch that will stop should the water reach a certain level, is this advisable, or does anyone have any ideas? Thank you again for responding, much food for thought

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I am also going to probably chop an ibc as well to make my grow beds now, half a plastic drum was a bad idea, not the best use of the space I have available


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Will leave advice on perch/redfin to European members. I have perch in my system but entirely different species.

2 x IBC fish tanks = about 1800 L water
2 x IBC grow beds = about 500 L wet media

Much better ratio and probably OK if careful with fish stocking. And even more OK with extra filtration, though still a lot of water cf some of the ratios you'll see quoted as good for beginners on this forum.

I can't give good advice about the filtration - I don't have the experience. But I'm not sure if a swirl filter usually has sponges and oyster shells in it - to be honest, I've never really understood the difference between swirl and radial flow filters.

With the above water volumes a sump may not be needed. Even if doing flood and drain with a bell syphon and both syphons get in perfect sync, you'll probably only have about 150 L (depends on media used) rise and fall in each tank. But I realise you intend it to be a biofilter too.

Might be an idea to draw a picture of how you propose to set up your system... the layout and if running constant flood or flood and drain with bell syphons (or standpipe with a hole and a timed pump). Then people can give good advice about how it will all work - including where to put the pump and if a float switch is needed.

Not sure if you've had a look at http://www.ibcofaquaponics.com - you could start your system with just one IBC - no need for sumps or filters. Simple and works well. Then expand your system once you've had a bit of experience.

Here is my proposed system, starting from the tanks, my logic is to connect the two tanks by using a pipe with holes placed at the bottom of the tank, this would essentially start placing water into tank 2 when the level rises in tank 1, similarly between tank 2 and the sump/bio filter, my plan is to incorporate some sort of solids filter at this stage, this somewhat filtered and biologically treated water will then be pumped into my grow beds (I'm aware that two tanks will require more beds hence the addition of filters), I intend to have these set up as flood and drain systems, in my understanding, this will further break down the ammonia and nitrites in the water before it is sent back into tank 1 to start the cycle again. A little different to my initial discussion design as I want to try have as few failure points as possible so figured I could remove the float switch. If my logic is correct, having a pump with a high enough capacity will ensure adequate water circulation in terms of quantity (quality is still yet to be determined but obviously depends on the number of fish in each tank). My aim is to try and have some nft included if I can and grow some strawberries, but this is a nice to have and not a have to, my main priority for the system will be the fish, hence wanting 2 tanks, but figured the veggies would be a nice addition to the system and the challenge will keep me out of trouble :p

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I reckon your planned set up looks very good and simple. It looks like those are solids lifting overflow (SLOs) pipes going from FT 1 to FT 2 and to the sump? That could be a good idea for removing the solid waste from the FTs but one thing to bear in mind is that if you have growbeds dumping into FT via a bell siphon this will cause turbulence and the SLO will be less effective as the waste will be moved around in the tank... I'm sure it could be made to work, but i think most people have timed f&d or constant flood with a spray bar in systems of these configurations for the SLO to work most effectively.

Trout and perch should be fine in the same system and even in the same tank as long as they are size graded, perch are voracious predators and will probably try to eat trout only a little smaller than themselves! Although probably better in seperate tanks to ensure both species are properly fed, or maybe trout would get to the food first etc. In the wild trout generally inhabit cold, clear, fast flowing streams and rivers, while perch inhabit slower moving murkier waters. So the trout will be a bit more sensitive to water quality parameters.

The amount of wet media you have in the system, ie surface area on which the nitrifying bacteria live, determines how many fish you can have, depending on size and metabolism. There should be around 25 litres of wet media for each plate sized fish. You could fill your sump with nylon netting or something to increase biofiltration, also if you do this you might be able to culture gammarus pulex aka scuds in there too, which are a great live food for fish.

Hiya soulchyld,
I would not recommend having a slo from one ft to the other. Better to have your gb drain header pipe split feeding each tank and each tank having each slo going directly to the sump. This way you are not transferring solids from one tank to the next and you can also isolate one of the tanks if required.

So if I used a constant flood system, I fear that the water will not really circulate if the water is fed into the GB from the top and the draining is done via a stand pipe also off the top, is this a reasonable concern? Silly idea also comes to mind but perhaps this is just that a "silly idea", for my spray bar that comes off of the GB and back into the tank, if I mounted a biggish diameter pipe horizontally with small holes on the bottom so that the water leaves the pipe slower than it enters from the GB could that double up as a nft to grow my strawberries, I know I would only get max 1m pipes off of each gb but hey 1m is better than no m right?

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The nft spray bar sounds cool, might be a bit fiddly to get the water distributed effectively along the length of the pipe, but I guess it's possible. You could ensure circulation with constant flood by dividing the inflow to the GB to each, or 2 corner(s) and placing a kind of hood tube over the standpipe with holes/notches in the bottom so the water enters at the bottom and flows up and out at the top; basically like a bell siphon that doesn't work!

Danny beat me to it... but will leave the post as originally typed.

Not sure how others run their constant flood. But I have mine set up just the same as a bell syphon setup - without the bell. Water flows in to my growbed at one end at the top. And out of the growbed at the other end via slots in the bottom of the housing around the standpipe. It's the growbed in the front right of the picture on the side of my posts.

A lot of people split their inflow so that it has two entry points on opposite sides of the growbed. But I haven't found it's needed. I occasionally drain my growbed by removing the standpipe. Not sure if it makes much difference but I'm hoping that this prevents anoxic spots and reduces buildup of areas blocked by solids.

If you build a bell syphon to start with (but don't glue the standpipe), you can run constant flood at first and switch to flood and drain any time you like.

Don't get me wrong... I've nothing against bell syphons. My other tank (back left) has a syphon that's been running faultlessly for years. Both systems work pretty well, though each has its adherents.

Not exactly sure what you envisage with your strawberry pipes... but, if nft, you might need to make sure that water is well filtered to avoid blockages in pipes. Could consider running a shallow version of deep water culture... ie pipes about half full of water... you can see some (if you have good eyes) hanging off the side of the back left growbed - better pictures in my thread. I started out using tubes and gutters and later switched to just tubes. I've managed to get three tiers of pipes running... so you might find you can manage more than 1 m on the side of an IBC.

Be aware that there has been some (mostly) friendly banter on this forum recently about jargon... ie what to call systems that aren't technically nft but also not standard dwc.

@dangerous Dave, how does your system cope with the cold? I'm concerned that having a spray bar going into the ft's could cause the water to freeze in winter? Unless I remove the spray bar when I think its too cold, my assumption at this point is that you rather have a slightly murky tank than dead fish! And they should not be eating that much in that kind of cold anyhow so I'm guessing even waste production will slow down? Also where did/do you source your perch? I will upload an updated diagram of my proposed setup for constructive criticism soon. Thank you all

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Having bell siphons dumping into the FT's won't create an issue with turbidity in the water. Having the solids stirred up will actually help with removing them from the FT's via the SLO's. Most people who run siphons that dump into FT's with SLO's, will set up the siphon returns/drains so that they create a swirl in the tank and actually move the solids around.

If you run bell siphons you will not have the potential fail points of timers, drain holes drilled near the base of the standpipes, the continual stopping and starting of the pump etc. You will also not have the issue of tracking and/or dead spots forming the GB's. Plus, on the cold frosty nights, when it's preferable to not have the GB's Flooding and Draining, you can remove the bell in the late afternoon, run it as CF all night, keeping the water and the root zone warmer, then in the morning drop the bell back in and you have F&D again.

If you have two IBC's and are concerned with maximising GB area and bio-filtration, as well as getting the gravel:water ratio more in balance, why not just simplify the design and build a dual IBC system, like that below?