Backyard Aquaponics
A place to discuss aquaponics

Back to the OP (if he's still around).

Get your PH as low as possible, it'll help the fish survive short term.

How much did 2200 fish cost? Sounds horribly expensive.

The folks I get my Tilapia from recommend a PH around 8.
M e wonders that having so many fish in such a small place, that the system basickly backwards cycled.
But with any water testing no one can tell.

Indeed it is.. but I dug up a very old one that was too hard for normal usage..
Yes... I pondered about plasticisers, but decided that I knew better
I would never use a new hose... oh the smell..
I have wondered about a blue garden hose, used for drinking water (camping usage)

Then the reality.. when first used with the first lot of Silvers, they survived for sooooo long.. near plate sized..
Had they died within weeks, then I would have looked at the hose as being a problem..

Thanks for the lateral thinking.. shows that you mind is ticking over the possibilities..

I MAY have got on top of it all, with another 99% water change.. ie. Where previous fish turned over at four days, I now have had some silvers in there for two weeks.. my AP Canaries ..
..
.peter

Catch 22
Make tilapia happy with a pH of 8, but kill them from Nitrite toxicitity, because it's said to be greatly accentuated at higher pH..

I would go for the lower pH at this stage, as a first-aid measure
..
.peter

PS.. and where is the OP... did we scare them off.???

Evolutionarysleeper

are you following the thread any more??
..
.

BuiDoi,do you mean Ammonia,at PH 8 Ammonia is in its unionised form and highly toxic to fish,but in this situation your trapped between a rock and a hard place,if you raised the PH as said the ammonia becomes more toxic,but you improved the efficiency of nitrification process,if we lower the PH the Ammonia becomes the less toxic form Ammonium,but we reduce the efficiency of the filter,at PH 6.5 it is said to be only 30% as efficient as at PH 7.2 which is the optimum level,so we have dangerous levels building due to inefficient nitrification.