Backyard Aquaponics
A place to discuss aquaponics

40 degrees plus = computer time
This is my idea, to be taken apart by you longtime aquaponic experts


First question: Is this somewhat right?
Second question: How many trouts or other fish will such a system be capable to carry if everything is sort of 'NORMAL' (Read a lot about what difficulties could arise in all those different circumstances).
My novice guess is about 20-25

Looks spot on to me Gran

20-25 fish would be a good start, you could push it out to 35-ish down the track I recon.

Is that only one IBC FT you have there. It isnt a lot of water for 25 fish . You will be safe with about 12 in that size tank.

Hello Gran. Pleased to see your stated gender now reflects the real you.
Just going through your schematic and I think you may have over estimated the volume of water in your growbeds by about 100-170L. This may prove to be significant at some point so thought that I would mention it now.

If you can have your grow beds drain into fish tank why do you need a sump tank? I would consider pumping from your fish tank to grow beds then drain to fish tank. The whole idea is to have the fish waste deposited to the grow beds in a efficient manner, no need to over complicate things. No need for a sump tank unless you have for another reason. Also get a air pump for the fish tank.


Edit: Spelling

Thanks for all your input. I just realized I made a typo the big GB (500ltr) apparently holds only 200ltr of water NOT 300.

CHARLIE: I think that would be really pushing it, 20 fish seems enough for us to start with, 25 trout I eventually buy (Where I don't know yet) since there will be some loss along the way if I go by what others have experienced.

PLJ Well, what shall I say, I rushed through the registering and noticed my mistake yesterday
Thanks for pointing out the discrepancy in water volume, it should have read 200ltr in big growbed. That should bring the total water volume closer to perfect? I corrected that image, please refresh page if it doesn't show

SEAMONKEY: Hm, somewhere in the depth of this forum the formula 3kg/100ltr floats around. To me as the novice that means 12 kg of hopefully happy fish in my estimated minimum of 400ltr water in IBC FT.......BUT.......that is kg, not fish if I am not mistaken?
My aim is to raise fingerlings (there will be losses on the way) to 300/400g and then start to harvest through to the last one which hopefully will not die of loneliness but end up in the pan as well. With these thoughts I ended up at the 20-25 fish.

THOMMO PERTH: My thoughts are hung on the idea of a constant water level in FT which I would not have when filling GBs from and drain into the FT, right?
Actually my thoughts are all over the place..................

Any thoughts are very much appreciated, up till now this is all theorie for me. The only thing that is there is the cleaned and cut IBC

If you run the system as constant flow the water level will remain at a constant level which should be full, just leave the pump on 24/7. When you visit BYAP you will see this there.

You can get trout from Troutman a member here, he does deliver to the metro area and he is very knowledgeable so you can pick his brains. lol I don't do trout, but I am sure there will be others here to give you good advice on them.

http://www.fergusonsprings.com/Fingerli ... rices.html

Sorry, for some reason I read your FT as 600L. Theres a couple of guidlines we recommend around here and that is 25 fish grown out to 500g per 500L of grow bed -and- 1 fish per 20L of water as a humane stock level per FT volume.

Using these safe guidlines, your GB capacity is 800L, this will support approx 40 odd fish grown out to 500g... although, your FT is quite small at 400L so the second guide overules the first so to speak. 20 x 500g fish in 400L is a safer stocking to stock humanely. Reducing that number to around 12 - 15 will see you fish grow bigger and happier and Id say that is what Seamonkey is suggesting.

Dont let all this get to you, it probably all looks like a bunch of numbers and it all gets confusing. Get into BYAP and it will all piece together for you once you get to look, touch and smell the systems in there. Faye, Nat and Sue will sort you out..

I will pop in to BYAP, was there a couple of weeks ago for the hydro pebbels and talked to a young man. Maybe it was you
CF would mean only one big hole for the IBC and not another one for the barrel, that is a tempting thought.

Well, as I said, up till now it is mostly all in my mind, but in our age there isn't too many trials and errors allowed anymore Better to have it as close to perfect right from the start. I wish we'd won Lotto. Would be much easier to buy a complete system and have it installed........on the bigger block........in the bigger greenhouse............:):) a girl is allowed to dream !

And yes, the numbers are currently driving my nuts. Gotta stay sane, gotta stay sane

Just another point I was thinking about:
CF system = one pump in FT, growbeds full of water FT full of water, water circles with air pump running.

Power failure

Water in growbed runs back to FT, FT overflow, appr. 320ltr water is lost

Wouldn't the new water disturb somehow the carefully nurtured bio system???

Not really, I have to add about 200l every 2 or 3 days to my system in this hot weather, I just run the hose into the end of a grow bed and let it drain into the fish tank that way. Seems to work ok so far.
On the air pump, get one with a back up battery in it so your fish will be ok if the power is off.

That's good to hear. No problem with top ups then.
The air pump I saw in your online shop looks identically to the one a retired aquarium friend would give me. But he said, it is only good for up to 200ltr tanks.
Would that be enough? The backflow would generate air bubbles as well wouldn't it?
Would be nice if I could use one that doesn't cost me anything

generally speaking, a lot of water splashing around your system should catch plenty of oxygen.
most of us who have a system running only have them as backup for power failure. it's like having a good glass of water for us to the fish in a bad situation. They don't need a lot of it so you don't really need a air pump. Only just when your system is not circulating. Even so, you shouldn't have them only on airpump too long because the poop buildup is still not good.

Thanks Jensilaedi, I guess the air pump I can get my hands for nothing will do the job then.
Better a bit more air than not enough.

Yeah it really depends on whether you are able to afford doing that or not. It definitely would be safer if they had an reliable supply of oxygen because of the existence of a pump. enjoy!

Id say that was Nat, he's a handsome chap.. I live in the goldfields and just help out online

Gran, If I lived in Perth, I would come to your house and set your system up for you.