They use to stay in the cave all day and only came out during lights out. I just decreased the lighting over the tank from 130 to 32 watts and now they are out more (2 of the 3 at least). The dominant one of the 3 still prefers to only come out at night. They are happy, healthy and a blast to watch! I would not worry about a possible decreased visual for clown loaches. I have gone several days without seeing them in the past. Sometime I hear them more than see them!
Scott
Scott