For people who don't know about the babies... – Fish Tycoon Free for iPad Review

You are only allowed to have 7 fish in the tank at one time so if you have 6 fish and get them all pregnant then only 1 baby fish is going to hatch. What I normally do is get all my fish pregnant and then put 3in the selling tank and put 3 in the normal tank. Hope this helped (:
Review by Fishes!!(: on Fish Tycoon Free for iPad.