I have a small pond that I have stocked with tilapia, 1100 plus 2 pregnant, 5 and 8 pound, females, with the plan of establishing a forage base for Peacock Bass. My plan was to have a self sustaining fishery.

I have an even smaller pond and the tilapia have thrived beyond every expectation, it has predators. That lead to the self sustaining idea.

The larger pond has yet to produce tilapia in numbers sufficient to support even one bass.

The two ponds are 100 feet apart in a similar position to the watershed. I feed in the small pond, not the larger. Lots of algae in the small, not the large. Lots of weeds in the large, not the small.

I have only one explanation, but was hoping for some thoughts, birds. The smaller pond is in front of my house where I occasionally have shortened the life span of a few unfortunate heron, bigger pond has no bird predators. But the birds are two species of heron, one kingfisher and little cormorants.

I'd say your birds have an impact but what about the fact that you feed the fish in the smallest pond and it has algae vs. macrophytes that are in the big pond? Don't tilapia prefer the algae as a food source? Does your smaller pond also have more nutrients due to the feeding?

The larger pond started with a lot of algae, then it slowly disappeared, which made me think everything was fine.

Then we had a renter who would throw a handful of food once a day or so and less than 20 fish showed up. They were to big for the birds to eat at that point.

The fish are mature enough to breed, but walking the edge no fry are in sight. There appears to be enough cover for them to avoid total wipe out from the birds, but since there aren't any, maybe not. I had a shelf a meter deep and a meter wide, built all around the pond for breeding.

The absence of fish and algae is where the problem is, just my guess. Now if I could guess the solution?