NetMax wrote:

Use 2 nets, chaser and catcher. Keep the catcher absolutely as still as
possible, until the last moment (if you even need to move it). Move the
chaser slowly corralling them. When they approach the catcher, a quick jerk
can sometimes send them flying into the catcher. Tetras instictively react
first to moving objects (this won't work as well with higher-order cichlids
;~).

My favorite trick is to put an irresistible food in a net close to the
surface, and wait. Shrimp pellets usually work pretty well. I just
pulled some gambusia out of the pond that way.

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