I have 1 male Black Convict that is about 14 cm, in my 150 liter tank. In the tank I got two 8-10 cm Rainbow cichlids, one 10 cm pike, and a 10 cm jurupari). My BC is the king of the tank, like a lion, he DOES NOT bother other fish at all. My guess is he isn't feel threatened by anyone else. He once crossbred with my Firemouth cichlid. He was a digger ever since I had him. A week after I bought the FM I saw all other fish in the top of the tank hiding, not from the BC but the FM. He wasn't aggressive but she was. The eggs were laid inside the PVC pipe. The first cluster of eggs (about 20-40) didn't hatch, but the second one did. I had a lot of fry, about 100. I took all other cichlids out except the parents. After about 3 weeks I took them out too. In this relationship the BC wasn't aggressive (at least I didn't see it) toward others even at time of breeding. He patrolled the PVC pipe, but the FM was always inside it and kept him out of it as well as others before I took all of them out. I put the BC and FM in separate tanks, which are close to one another, and the BC keeps looking at the glass on the other tank for FM. It should be noted that after much thinking I found it to be unethical to breed hybrids and I feed the fry as food for my other cichlids, my pikes liked them. I never planned them to crossbreed and it was a little surprising for me. But it shows you that Convicts are very adaptable fish, they are true survivors.
This is, in my opinion, one of the top five coolest of all tropical fish. Though they are not the most beautiful, they are pretty. But it is their behaviour (intelligence and character) that make them so fascinating. It is mainly the way they behave when breeding or wooing a mate. (The males a great "wooers" - they really put on a show). The irony about this fish is that they are called "garbage fish" by many people because they breed like crazy and are hard to get rid of. No matter to me. I don't have fish to impress anybody. I setup my tank to make sure that most fry get eaten and only the most fit carve out the few secure territories in the tank. My other carnivorous cichlids eat all but the smartest, toughest, and otherwise fittest fish. Out of every spawn of hundreds, only one or two ultimately win their survival. This might seem cruel but it is good for the breed and it allows you to observe the whole fascinating spectacle that a convict family produces, without having hundreds of so called "garbage" fish to unload.
The convict is, to me, very easy to breed. In previous experiences I had a breeding pair that took a few tries to get it right. My advice is, if you don't have a huge tank or a spare, leave them with the parents. The parents will help keep debris from getting caught up on the eggs and causing them to rot. If eggs do manage to rot, the parent most likely will destroy them. Also, a little table salt and clean water might help a little bit on keeping eggs fungus free.
If you like beautiful, and really aggressive fish, these are the fish for you! Mine is fearless - she bites at my fingers when I put them in the tank, and has ripped the lips off of cichlid tankmates. These are VERY territorial fish, so putting them with fish that aren't like-minded is basically giving them some fancy feeder fish :)
I have 2 black convicts in a 200 L aquarium. They are kept with 4 tiger barbs, 1 kisser, 2 electric yellows, 1 catfish, and 1 large snail. Everything was great, in the beginning. They were bullied around by my tiger barbs. I couldn't believe the stories about them being mean. Well, it turns out they were male/female. They began breeding and their first batch of eggs died. Only 2 hatched...how sad. They still weren't aggressive. But then there came the 2nd batch. Once the eggs hatched the female killed one of the electric yellows (the one that wouldn't get away from her nest). The female also chased away the male. She keeps all the other fish in the aquarium, including the male, on the other side of the tank! She has also killed the kisser fish. She herds her little babies around the tank and bullies everyone around. I don't think I will let her have more babies in this aquarium.
My roomate and I had a beautiful breeding pair of convicts in a mixed cichlid tank. Unexpectedly, the momma died. After that the male, who used to be the king of the tank, became very depressed. He now gets his @$$ kicked all the time and can't hold on to a territory. He doesn't even try. We got him an immature female which we hope will cheer him up soon. We are so amazed at the intricate social behaviors of these fish. Rest in peace Momma.
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