Backyard Aquaponics
A place to discuss aquaponics

Guys

Wanted to run through my plans for my first system. All the information I have is predominantly gathered from these forums and your views would be appreciated. Its smallish however I want to start this Monday once I pick up 2 - 3 IBC's (for free) and I dont want to bugger the IBC's up. After cleaning them out (have mineral oil in them), will let they dry out for a few days then start

FT
- 1 X IBC with the top cut out. This will allow almost 1000 litres of water capacity and hopefully not to much temperature variation. Will wrap in shade cloth to keep stable and cut out UV
- approx 3,500 ltr per hr submersible pump. Will feed the GB (via Ball Valve) and allow another outlet (with Ball Valve) so I can feed back into the FT for water movement & aeration. Size allows for expansion
- 1 x 2,000 ltr per hr aquarium air pump (thoughts?) with 4 - 6 stones hooked up to a UPS that will assist with aeration and incase of Power blackout, will stay on with no power for approx 6 hrs

GB
- 1 X IBC cut in half then trimmed up (top & bottom) to allow for 2 x grow beds of approx 600 - 650 litres
- GB's will be basically on top of the FT
- 15 - 20 mm stones of some discription
- Siphon will be 2 x äffnan designed Bell siphons (1 in each GB) made by myself
- Water continously flowing - 24/7 (however, may turn off for 6 hrs overnight. 4 mm hole in bottom of siphon to ensure it will drain)

Misc
- Fish - will start with approx 40 trout (to 1000 ltrs water) as the Tooperang Trout Farm is 10 mins up the road
- Temperature - unit with outside and water temp digitally displayed
- Test kit: ability to check Ph, ammonia, Nitrate & Nitrite
- Seasol & Power Feed to be added when/if required

Future stuff
- Backup power switch with 12 v battery and bilge pump
- new FT & GT - greater capacity

Miss anything?

Cheers all for your time

Everything is great, but too many fish for a start up.

Go 25 at the most, your water will be crap quality for a few months.

As said, everything else looks good, well done.

cheers

I suppose till the cycling is done and quality is up, it could be a risk so I would tend to agree

Once the quality is up, what would you suggest for a 1000 ltr FT? I would think 50 - 60 should be ok?

Water amount is not the problem, it is the filtration. 3kg of fish per 100 litres of growbed (in a mature system) is something to aim for.

so lets say 600 litres of gravel = 18kg of fish, or around 35-40 fish.

thankyou - clearer now so the 40 number should be ok once it matures

Yes, and no.... 30-40 fish.... weighing 500gms... 15-20kg total....

Not 30-40 fish approaching 1kg each... unless you double your growbed capacity...

600L of growbed... is still only 600L of growbed... and ... at best... only capable of filtering 15-20kg...

And I stress...at best.... 40 rapidly growing fish, feeding heavily... in about 800L of fish tank... with 600L of growbed... is going to always be on a knife edge...

With double your growbed capacity (1200L).... you've got some margin of error... and control...

Your trout will grow beyond 500gm within six months.... and I wouldn't count a six month old system ... as "mature"...

I just can't understand why people continually attempt to, or suggest... double the stocking density... while halving the recommended filtration capacity... which was always 2:1... not 1:1... especially in a new system....

Personally... for 40 fish... I'd suggest a minimum of 1500L of growbed....

Thanks Rupert

The plan was to introduce more GB and to get it way past a 1:1 once the fish are about 2 - 3 month (admit, did not add this to the plan), be at least another 300 litres if not more

Stocking is purely based on what Murray Hallam suggests - of a safe ratio of 1 fish to 10 litres of water (maximum). He also suggests a "safe volume for a home system" of 1:1. So with 600 litres of GB, one would assume (once matured) that 60 fish in that system would be ok. Agree that in the early days, to ensure you can deal with water quality issues easier, less is better at the moment. For me, I will get 25 - 30 and I do understand why I need to do this however I will add another 300 litre GB within the month.

Also, my understanding & working out is the trout will grow to approx 500 grams which is when I will eat them (as different to 1 kg each). I also agree the water will not be 1000 litres, as I dont have a sump (yet - or a CHOP System), my capacity would be approx +600 litres

Thanks for your info