What is the capacity of your biological filter (i.e. what's the filter rated for)?

What species of tilapia do you have in the tank?

Both Ammonia and Nitrite readings were the same at .25ppm?

So you're estimating that there's about 150# of Tilapia in there now?

How large do you want to grow the Tilapia before removing them from the tank?

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).