IHMO, you didn't stock enough. Time will tell. Here, in Northern Indiana, I have found that ALL visible algae has to be killed 5-7 days pre or post stocking of Tilapia, and the best size Tilapia to stock are 4-9 per pound. If 40 pounds per surface acre isn't stocked, or the the algae isn't killed (removed like Bill said is best) then it's like they weren't stocked at all.

Don't think "Oh, I don't have to kill it, I'll just stock more per acre." Bob Lusk commented that they stocked 100#/acre without killing the algae and they didn't do anything, and I duplicated that one year with the same results.

Cutrine Plus liquid for water <24" deep, Cutrine Plus granules for deeper water is what I recommend to all our customers. Follow application instructions on the container or bag.

Stocking 1#+ adults doesn't get the results that stocking smaller fish do, and if the Tilapia are food grade and not 50/50 male/female then you will not see the algae control either. The 90-10 food grade sex mix really doesn't work well at all.

We also got bit one year by stocking the Tilapia in water that was in the low 60°F range. A prolonged cold front rolled in, water temps dropped to the low 50's and we replaced a LOT of dead Tilapia. Now we won't stock Tilapia until water temps at 2' water depth are 70°F.

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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).