I recently bought 6 of them. THEN I found out with some help from the good people on here that they are a nuisance so I took them back to the LFS. The reasons they are sometimes not good as far as I have gathered are:
1) They eat loads of algae when young but when older (2-3"?) they go off eating algae and you need to feed them as you would other fish.
2) When young they are cute and endearing and zip about all over the place keeping themselves amused. When older they get aggressive towards their own kind and other similar fish (flying foxes, corys, etc) and become very territorial.
3) When older, they can take to attaching themselves to the side of other flat sided, slow moving fish such as angels, gouramis and discus and will suck the slime coat off of the fish. Considerable damage is done to the 'victim' and great stress is cased. Remember, the loach can suck on hard enough to hold its own body weight up and the 'victim' fish has no means of pulling it off.........
4) They are known to eat the eyes of other fish. Apparently cories are most often victims of this.
So I hence I took mine back ASAP. I think if you just have one and chose the other inhabitants with care you may have a good fish.......
If I'm wrong about any of this I'm sure someone will set the record straight. Ask at your LFS - as you already have the fish they may give you proper balanced advice.