What kind of lizard is it? My beardie never leaves uneaten crickets no matter how many I put in there. I just keep a plastic critter keeper for my crickets. I buy the large jar of powdered cricket food and water bites. Both fortified with calcium and vitamins so I rarely ever dust the crickets. If there were any left over you could use the fish net idea but its not needed. If there is a couple pieces of greens left in the enclosure the crickets will nibble on this instead of your lizard. The crickets will eat anything actually. A small slice of potato will attract them and prevent nibbling on a lizard tail. Even a few pieces of dry lizard food. A potato chip ir a corn chip. Whatever you have in your pantry. Doesnt matter. If you are worried about your lizard getting nibbled on and dont want to fish out crickets just drop some morsel of food in there for them to nibble instead.