My White Brook farm, White Nile tilapia are 8 months old and are very vigorous and healthy looking. I am hoping they will start to reproduce. The dominant male is about 10" and some of the females are over a foot long. I think my main problem is that my 125g tank is a bit too crowded for spawning. There are nesting males at both ends of the tank and all the rest get chased and crowd the middle. There are 20 fish in there. I have another 75g tank that I moved a few fish into to reduce the crowd but still the big tank seems too crowded. So, I am going to reduce my numbers and keep some of the biggest, healthiest fish in there for breeding.
Here's my main question though. The male tends to make his next right near the water intake of my overflow system. I have tried putting filter material on it but it always clogs up. Does anyone have troubles with the eggs or fry getting sucked into the intakes? I am wondering how much effort to spend trying to get the intake as far away from the nest as possible. I use an overflow system with the intake on the bottom of the tank to bring out the solids. I guess I could switch it to the top or keep trying to block it off without clogging. Any thoughts on this?
I move pregnant females to a 20 gallon tank for a month to recover and put on some weight. Don't chase the ladies with a net, just slowly maneuver until she accidentally slips into the net. She will probably spit out many of the fry in the net.
I put her in a bucket gently washing fry out of the net. You can then pick up the female by hand - a wet cotton glove makes this easier - open her mouth and swish around in the water to wash out any remaining babies. Then place the female into the tank by herself. I use a fry net tank hanging on the edge of the 20 gal tank to house the fry.
Using this process removes the sucked into the filter problem. Small fry are isolated in a net until large enough to not have a problem with the filter siphon. I also use sponge filters to augment the siphon filter. Fry food fouls the water in a small tank pretty quickly. I change 50% of the water ever couple of days in the fry tank. 300 fingerlings need water change daily.