Tips on removing a Goby from my tank

I have a 90 gallon setup that currently has a few fish in it that I am going to
be moving to a different tank. Does anyone have suggestions on catching a
spotted prawn goby ( approx 4-5 inches ) without tearing about the rock
structure and such. I have seen traps on various websites but wonder if they
will be usefull to target a particular fish.

The easiest way for me catch a fish is at night, with all lights off
for an hour, use a flash to locate the fish then turn the light on,
fishes will freeze for a moment, just use the net to catch, they dont
even see it coming (actually I can catch them by hand). Good luck.

Thanks for the Tip