How to catch a fish?

My current tank has three Cardinals and two of them are bullying my smaller one along with a Goby. As all of you know they caught onto the net and swim for cover. They are very aggressive when feeding and swim to the top but my Blue Tang and Percula do to so I don't want to mistakenly catch and stress them. What tips/tricks do you guys have for getting those suckers out of the tank? I've read coke bottles have been used but I haven't seen instructions.
Thanks for the input.

 

I know coke bottles work, but I had very lil luck with that.. I think the best way to catch them is either when you are feeding them you can get them with the need if you catch the tang at the same time you can always release him it shouldnt be too stressful.. normally I use two nets to try and get them where I want them, the other option is do it at night when your moonlight are out you can probably get them easier in such manner.

 

Honestly without a fish trap this is the only method i have found to work for me = I will place a net with food in it in a low-flow area of the tank and leave it there. Leave it there as long as you need to get the fish used to being in it in the tank.... and then once they get lackadaisical swoop them up into the net when theyre eating!!!