Fish Id Please?

[DragonLass]

I was at the dentist a couple of days ago, and in the waiting room they had a big fish tank with several nice cichlids and other various fish.
One fish that really caught my eye though was what seemed to be a catfish or maybe a loach. It was a jet black colour, and had a brilliant pink tail. I have a feeling though that the tail may have been painted or dyed somehow.
It was browsing around eating algae. It had a mouth underneath its nose, and the nose itself was kind of skinny and long.
It definately wasn't a black ghost knife.
Anyone got any ideas what it is?

 

[The-Wolf]

RTBS
red tail black shark

 

[Katchan]

Possibly a RTBS wolf but it sounds a bit strange that the tail was pink with a jet black body, usually with red tails if their tail is pink then their body is a washed out grey indicating major stress. But if the body was jet black the tail should of been vivid red/orange?

Andrew

 

[The-Wolf]

I took pink to be poetic license and the actual colour was red