How to catch a Damsel

I would try the krill in the net idea first.

I've caught a Sixline Wrasse, Hawkfish and a CB Angelfish by leaving a net in the tank until they're not freaked out by it. Basically I sit the net in the tank so its a bit away from the front glass (so a gap is left and the fish can swim between the front glass and the net), and leave it there for a day or two. Next day I put the fishes favourite food in (or in front of) of the net (without moving the net) and wait. It might take a little while but usually they'll just swim in and around the net, because they've got used to it being there, and try and get the food.
 
Well my idea worked! My devil damsel swam right in the net after the krill. It's a good thing too, I had the spear gun as my backup plan.
 
the only thing that will work without tearing the rock work down is a fish trap that you buy over the internet
 
the krill idea is your best bet, ive caught a damsel in a similar way i just started feeding him by attaching his food to a safety pin that was suspended by a rope and wen he got used to that i put in in a plastic ziplock bag (still attached to the safety pin rope thingy) and tada i had him!
 
yeah the fish trap wouldnt work for banggais because they dont really swim and explore a whole lot...
 
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