Well, let me 1st say black sharks are awsome! He is my favorite fish, they've got lots of personality and they get huge. That said, they have attitudes to match. I think the best tankmates for black sharks are cichlids, fish that are able to take a beating. The african cichlids and smaller CA cichlids like dempsey's, convicts and GT's are great tank mates because they are a lot smaller than a black shark, when the shark gets moody and chases em they can get out of his way or hide really easy if you have some caves so he's never done any damage to any of the africans or smaller CA cichlids other than just chasing them around because he cant really catch them lol The problem with the jaguire cichlid was his size, you know jags get to be 16 inches themselves, there was nowhere really that he could hide from the shark, and especially around feeding time the shark would just go crazy on him, he would wind up and hit him so hard I swear you could hear the thud through the glass. His relationship to with the Red Devil is weird, you'd think they would fight but they are COMPLETLY docile with each other. Sometimes Ill turn on the lights in the morning and the Shark and the Devil are sitting there huddled up togeather like best of friends lol So yeah, they are pretty agressive fish, he has chased everything Ive ever put in that tank except the red devil with whom he seems to really like and vice versa, they are kinda like bigger more agressive versions of the red tail sharks and Im sure if you've had one of those you know how pissy they can get lol. Anyway, if you have a big enough tank, dont let their agressiveness put you off from getting one, Im telling you as a fish hobbyist of 15 years you wont find many other freshwater fish as spectacular and rewarding as an adult black shark!!!!!!!!!!!!
PS Ive got a leporinus also that he dosent seem to mind at all so those would be really good tankmates for a BS as well!!
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