Yes it does depend on the size of the tank, and whether the OP would like to keep one or not. I am sure that the OP will consider such fundamentals. Also remember that Clown Loaches take a very loooooong time to grow large, and can remain under 3 inches for a couple of years in a modest sized tank.
Also small loaches can do the job. I had two small CLs gang up and kill a Malayan snail on the first day I put it in there (not anticipating that outcome, of course). The snail was at least as large as they were!
I am quite sure that loaches do not view the activity as 'janitorial duties', but are utterly delighted to find themselves in a Garden of Fishy Eden.
Finley