Yeah I do the same as Jon. Or I have been known to do what Matt always says. Get them while they are sleeping. Dark room, turn lights on and catch quickly. LOL
Took me a few months and at least a half dozen attempts (traps, tank drained, etc.) to catch my last Crosshatch algae eater out of the 33... The first two were a cinch, but once I was down to 1... ugh.