eaten convict fry

what else is in the tank?
 
so you have a pair of convicts and a pair of jewels in a 30 gallon?

there must be a huge ammount of fighting going on in there. those are two pretty aggressive cichlids put and overcrowded in a 30 gallon, plus they are breeding pairs, which adds to the aggression.
 
I agree with jm1212. Overcrowding with two breeding pairs in a small tank will lead to hyper-aggression, and is likely why your spawns have been unsuccessful. Frankly, you're very lucky they haven't wounded or killed each other.
 
put the jewels in a different tank
 
Even with the Jewels im surprised the convicts arent rearing any fry...the dang things are like rabbits...they seem to infest any tank I add them too...even with much bigger and aggresive fish than jewels (RD's and Jag's).
Having said that...they are great fun to keep and pound for pound are one of the toughest fish onthe planet...ive seen a breeding pair contain 3 very large oscars & a Midas (all about 25cm) to about 3 square inches of water in the back top corner of the tank!
Jewels(from west africa) dont realy go with Convicts (nicaragua, central america) [though they suit the same sort of conditions] and I agree with rbishop they would be bettter in a different tank (the convicts dont need the space so much as the Jewels)
 
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