Backyard Aquaponics
A place to discuss aquaponics

Hi again guys & gals got few questions

1. I got 40 tilapia about 5-8" long in a 1L ibc FT with 2 ibc GB 1 sump and a RFF... is a reading of 80+ to high for tilapia fishes its no where close o the max reading of the api kit of 160... should i be worried at this time?

2. I got a third GB i want to add to the system would the ammonia and nitrites rise in the system and what i could do to protect my fishes?

A Nitrate level of 80ppm definitely wouldn't be an issue for Tilapia, but does point to the fact your system is overstocked. I suggest to my customers that constant levels over 40ppm means they need more plants, or less fish. At 60-80ppm some plants, especially lettuce may start becoming bitter. A level of 160ppm inhibits seedling growth in many plants and can cause issues with fruiting plants not producing.

The Ammonia and Nitrite will rise if you don't add the third GB. Adding it won't increase the levels. I would add it a.s.a.p, and for 40 Tilapia, possibly a fourth, depending of course on your GB gravel depth and total wet gravel (bio-filtration) volume.

Mr Damage Thanks for the valuable info I think to buy myself some time i will do a 50% water change to add the 3rd GB and prepare a 4th and 5th as wall again thanks for the help and info!