yes i tryed feeding them and trying catch them with a net but they will again swim bk in to the rockDo they generaly come to the surface when you feed them?
You're trying to catch a damselfish with rock still in the tank? Wow, good luck... About your only hope is a product called "The Trap". Its an acrylic cylinder with a place to put food as bait and a trap door. COLOSSAL pain in the butt to use but it works. May take you days to try and get them though. Failing that you can try fishing, literally. Get the smallest hook you can find, skewer a bristle worm, and do it old-fashioned. Or... Take the rock out of the tank
I often was able to pull my damsel out by getting a larger net than you would use and then putting a block of frozen mysis shrimp in it. Then when the fish comes in to feed swish it out.