Name: Epalzeorhynchos bicolor
Origin: Thailand (Me Nam R.)
The Epalzeorhynchos bicolor (formerly Labeo bicolor and often misspelled as Epalzeorhynchus bicolor) is a popular fish added to community and Asian biotope aquariums. It has a pitch black body color and only the tail is red. When healthy, the colors look so great that it can easily be confused with a marine fish. As with other Labeo's, it tends to be intolerant towards its own kind (which makes breeding these fish extremely difficult).
My sister has always been a fan of red-tailed black sharks, so I got her one for her birthday last year. He lived in our 68 gal community tank with some tetras, gouramis, cories and livebearers. He was only 2.5" long and very small when I bought him, but after about 7 months, he'd grown over 5" long and filled out a lot. He was one magnificent fish! But he was also one nasty fish and when he wasn't hiding, he would chase his tank mates around mercylessly. He even caused some injuries resulting in deaths. My sister did some phoning around and managed to land Wilcy a home in the Vancouver Aquarium! So now our community can swim in peace, and we can rest assured that Wilcy is getting the best of care!
My red tailed shark mercilessly harassed and mutilated every other fish in the tank until I moved it to another tank full of obnoxious tiger barbs. hahaha. Now, surrounded by fast, aggressive fish, it seems to have calmed down. Moral: many fish are labelled "community fish", but it really depends what kind of community you have.
Mr. Red-tailed Shark is one of my favorite pets. He loves his caves, and pals around peaceably with Mr. Clown Loach. He does not harrass my tetras, but perhaps that's because he learned that he wasn't Mr. Big in the Mated Pair of Kribensis School of hard knocks! But even in his new home, he still hates Chinese Algae Eaters of all ages!
I also own a red tailed shark for a little over two years. He has definitely gotten bigger (I'd say about 3 inches nose to tail), but certainly not a huge growth spurt like Audra mentioned of her sister's. He was in the community tank too, and did well for 1 1/2 years. Then he too got too big for his britches, so rather than give him up (he's my favorite), I've put him in his own home. He's beautiful though.
I too have enjoyed this fine fish. I adopted mine (3) from a neighbor that had to move some distance (out of state). I was not sure how the three adopties (3 1/2") would do in a tank (125gal) full of cichlids. They did just fine. As a matter of fact their color became more brilliant and they quickly became buddies with my two clown loaches (5 ½" & 6 ½"). I never had a problem with illness or terrorism from any of the three. I miss them now that they have passed on and stop to look at them in every pet store I visit.
Males have a right angle in the tip of the dorsal fin. Females do not have the right angle. Their dorsal will come straight back, more like one side of a triangle.