Backyard Aquaponics
A place to discuss aquaponics

Hi

I was wondering I have just watched Murray Hallam's Easy Aquaponics DVD and he said that as a rule of thumb the fish stocking can be 1 fish per 10 litres of water. I have an IBC tank using the CHOP system with one half of a 200L blue barrel cut lengthways for the growbed and another cut horizontaly for the sump. I am thinking of expanding to at least 4 or 5 half barrels for growbeds before I get any fish.

According to the rule i could have 100 fish but I want to half that because it is a new setup but in the DVD he said it is good to have a 1:1 ratio of growbed volume to fishtank. Does the rule of thumb only apply if you have a 1:1 ratio? If I had 5 barrel half that would be 500L in volume of growbed so the ratio would only be 1:2 which I doubt is enough if I added 50 fish. I was thinking is I added 25 fish with 5 barrel growbeds because I only have half the ratio so maybe half the fish?

Any thoughts, comments, or queries will be acknowledged.

Still in development stage but just thinking about the future.

Hi Keriaf, thats a little heavy at those rates I think.

Try reading through this thread, these figures are a bit safer. viewtopic.php?f=12&t=6646

I think you'll find that Murray has now modified suggested stocking rates to be more like 30kg of fish per 1000L... or 3kg/100L.... with a minimum of a 1:1 fish tank to growbed ratio...

A 1:1 ratio.... is the bare minimum... anything less and you must stock to your filtration capacity... which is generally your growbed capacity...

With a total of 6 half barrels... you would have about 600L of filtration.... so a max of 20 fish at 1kg...

Or IF, and I stress "if" you genuinely are going to start eating your fish REGULARLY at around 500gm... you could perhaps double that....

But in a new system... I would suggest you start with 30 fish max...

I had a question about where that rule of thumb (3kg / 100L) came from. Is that something scientific? Or something the AP community has worked out via personal experiences?

Thank you to all contributors, it has cleaned up my questions.

Thanks to all for the very quick replies.