While net breeders can keep fry from being eaten, I'm not so sure the babies totally thrive in such an environment. I have had the opportunity to observe a molly fry and some Swordtail
fry. The molly is the last from an ill-fated molly who died after giving birth, I think prematurely. There were three Swordtail
fry in my other tank. Two i fished out of the filter and put in the net, the other was loose in the tank and I could not get it without a major disruption, so I let it alone. Fast forward about a week and a half. The Swordtail
fry loose in the tank is doing much better than the two in the net. This morning I shook the 'net' babies out into the tank. I am debating whether or not to release the molly fry. It does not appear to be growing at all anymore. Two Platy
fry that managed to survive in the tank are growing fast and are really starting to look like mickey mouse platies. The molly fry is only about 3/8 inch long or less and has been in that net breeder for a couple of months at least. The platies were born and have surpassed the molly in less than half the time. If I release it into the tank, I'm sure it will get eaten, but given the evidence that fry do not thrive in this environment I think and feel I have no choice. I do not have a hospital tank or quarantine tank. I have three tanks and there is a limit to what I can do. Just an observation.