The worms are pretty small or in rocks, nooks, sand, etc. You may see an arm or tentacle out and about but I don't think a laser is the way to go. I was watching my fox face rabbit the other day picking on some rocks. It accidentally got one here or there and it would try and suck it up like a spaghetti noodle - no pun intended. It just retracted and there today.
I have, literally, thousands of these things in my tank. Maybe not thousands but maybe - let us just lay lots. The only time it is annoying is when they float around (which is daily at the moment). I have nothing that eats them so the population control is self controlled by the abundance of food or lack there of. They are in the sand, rocks, sump, overflow, etc. I just let them be because as the tank matures and I add coral I really won't notice them.
They do wonders eating left over food and other decay so I can't complain. But to the post I don't think I laser is going to work unless you mount it on a fishes head with some crazy Stark nano technology and train it to be a super awesome sauce underwater assassin