I have this question that's probably really dumb, but- I was looking at the pics of red-tailed black sharks, and orange-finned loaches ( on www.aquahobby.com )

and I can't tell the difference, apart from the fin colour !!

so I dunno if what I'm seeing at my LFS is a loach or a shark with red fins too...

HELP ? (the lady in charge of the store isn't around, so cant ask her )

Its hard to tell from those photos

but if you look closely they are quite different... sharks have more elongated and slimmer bodies than loaches. You can also see that the loach is completely flat on the bottom. In the case of the pictures you saw, the orange fin loach has all its fins orange... while the red tail shard has all black except the tail. If you are at the LFS and still in doubt, just look for the most common loach: the clown loach... the orange finned loach will have exactly the same shape

OKeyy