Clown loaches

you need a huge tank to keep them happily. They like to be in groups, and have been known to grow up to 16 inches. Keeping a few 16 inch fish in a group requires a pretty large tank.
 
Botia striata, b. histrionica, b. kubotai or y. sidthimunki would be a good choice for a 55g. Yoyos grow pretty fast to ~4 inches. Whatever species, get at least 6, they are all very social.
 
you can have a lot of clown loaches in a 55 with good filtration when they are small ... they grow very very slowly. Clowns in my opinion are one of the few fish that like to be overstocked. Yes in the future you will need a much larger tank but you can hold a lot of small 1 to 2 inch clowns in a 55 gallon for a while

check out ewurms blogs on mfk

http://www.monsterfishkeepers.com/forums/blog.php?u=6647
 
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