Culture some live foods in your back yard. Mosquitoe larvae are regularly found in buckets of water sitting outside under trees. If there are leaves in the buckets then you get more mozzie larvae.
It is illegal to culture mosquitoes in most countries due to the diseases they spread, but if you happen to leave a few buckets outside, and some leaves fell in them, then the sprinklers or rain filled the buckets up, well, that's not your fault. And if some mozzie larvae happen to appear in the buckets, well you scoop them out with a fine mesh net, rinse them under a tap and feed them to your fish.
Daphnia can be grown in the cooler parts of the year and are a great live food. They can be put into tanks when you go on holiday and the fish will eat them while you're away. Unfortunately they get sucked up power filters so last longer in tanks with air operated filters.
Some female cichlids have gathered up live daphnia and started protecting them like they do with their babies.
Rotifers can also be cultured and will live in tanks until they get eaten.
The following link has information on culturing live foods for baby fish, but includes Daphnia and some other creatures.
https://www.fishforums.net/threads/back-to-basics-when-breeding-fish.448304/
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You can collect up fruit flies, midges and aphids when they are plentiful and freeze them in plastic bags. Then use them as food over the next few months.