Step 1: Take out all (well, most of) your rocks
Step 2: Take two nets and proceed to get very, very wet.
Step 3: Relish in your victory for a moment (or catch your breath, call it what you will)
Step 4: Dry the living room carpet
A clear plastic bag makes it easier, but not for catching a fish for venting.
People say catch them at night, but I've found that I need room lights on for me to get them, and within moments they're awake enough (or the one I want sleeps in a cave) to completely eliminate the bonus.
Catching while feeding doesn't help me much either, they just get skittish and suspicious of food for a day or so.
...and I have a 'little' 55 :lol:
Luckily I've only had to do this twice in three months. Once to take back the petshop advice auratus, and once to help a poor female lab.