All I do know is this. When I put the dwarf corys in thre fry tank, I had larger survival rates in the spawn tank, and less missing ventrals on 2 consecutive spawns. I was given the challenge to try it before disbelieving it. I accepted the challenge, and was pleased with the outcome. If you never try it, you will not be able to truly say it does not work. If you choose to not believe it before trying it, then I hope you will find another way to help the problem, because there doesn't seem to be any better answer to this point.
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