Red-tailed Black Shark

[RyJ]

I'm wondering if this fish is too aggressive for a 20 gallon tank with Cardinals? Has anyone had success keeping these beautiful fish in a community aquarium?

It will only be in the tank for a few months...as it will out grow the tank!!

[clayt101]

I've never had problems with that combo. IME they go after fish that are similarly shaped, dark in color, or bettas.

[Bantam]

i agree with the above. mine chases the bala sharks he's in with but ignores everyone else. having said that he doesn't like new additions to the tank though.

[val]

I had three RTBS's. None ever bothered any of t he fish I had, from barbs to bettas to assorted gouramis. Now, I would think the 10g tank would be too small. Don't keep him in there too long, my RTBS's were always on the go, cruising very fast and they appreciate a long expanse in which to swim...

Val

[online2]

Would agree with Bantam, my RTS of about 6 years does not like new tank mates, it took about month for mine to get use to my 3 clown loaches. He still gives my black Skirt tetra 3 sec chase from time to time, but never does any harm. I would think 20g tank is to small, I think 30g is the smallest recommend. Mine seems to be better now that RTS went from 30 to 55gal, even looks like he pick up some more size. Great fish but needs space.

[niner9]

I have my rts in with pearl gouramis, neon tetras, white clouds, yo-yos, and kribs. I had two angels and a b. ram but I moved them to their own tank now, and he doesn't bother anybody ( now in a 55 ), but when I had him in 30gal., with the gouramis, white clouds, and neons, he was fine until he reached about 4" then he started to torement the gouramis pretty bad. Then I added 2 weather louches which he absolutely hated. everytime they came out from under a rock he would nail them. Hit them so hard you could hear it from the other side of the room. Needless to say I returned the louches.

Moved them all over to a 55 and added the aboved mentioned fish, oh yah there is a rubber pelco in there to and some ottos i forgot about and all is fine. IMO, I would draw the conclusion that even a 30 is a bit small. I find rts tend to get bored and thus chase fish. I would go into greater detail to explain why I think this, but my post is already long winded enough. Mine loves to play in my power head. I think a general rule of thumb with a rt the longer the tank the better or lots of fast current. Just my opion though. They are super cool fish mine is just over 6" from head to tail and would recommend one to anyone, but I do think it would require a little mor space than a 20 gal, would give. niner

[AikidoGuy]

good tough and attractive fish. i have a full grown one that is probably 5 years old. It has been with small tetras like neons and the like. it is now sharing a tank with a F1 female Festae, Midas, and a female fenestratum. the shark takes a beating and is very quick when its had enough. good fish works well in alot of setups.. i believe this fish is extinct in the wild too.

[Weasel6]

I've got a RTBS in my 75 with various other fish. He's great. I call him "Jack" because he cruises around all day sucking on just about everything looking for algae or something and when he does, his mouth is like a jackhammer. He doesn't bother anybody except occasionally a tiger barb will aggravate him for kicks and when he's had enough he'll chase that one around for a bit and then thats it. Mine is very attractive with his jet black body very red tail. Great fish.