I can't seem to catch my damselfish. I have tried tricking him with food, pushing min away from hidding places, among many other things that yielded no results. Does anyone know of anyway to catch him without pulling all of the live rock from the tank?
two nets isn't really going to help (although I like the input), only because he can swim into the live rock in various places that the net is too big for. I would prefer not to disturb the live rock. As for the BB - that's hysterical!! My husband and I are both cracking up! LOL 
How big is this fish? Try getting a 2-3 liter soda bottle and cutting off the top part, just where it begins to become straight along the sides (you'll end up with a piece that looks like a funnel and one that looks like a wide-mouthed vase). Cut off the very top so it's large enough for the damsel to fit through, but not much space to spare. Invert the top and put it into the bottom of the bottle and drop some of the damsel's favorite food inside. Put this in the tank and allow to fill with water. You may need to add something for weight so it doesn't float. When the damsel eneter through the "funnel" to get the food, it will tend to follow the sides to find a wat out, and just find the "corners" where the two pieces come together. See link for pictures: http://www.floridadriftwood.com/fish_trap.htm
If your damsel is too smart or too large for this, you can try the same with a wide-mouthed jar and string around the neck. You'll have to be fast, though, to stand the jar upright and lift it out of the water (and put a lid on it so the fish doesn't jump). Lowering the water level can help, as long as you don't expose any live rock if you have it in the tank.
The only choice you have after all these is to deconstruct any caves so there's nowhere to hide, and use two nets (and maybe another person) to try and trap it in a corner.
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