How to stop Betta from stealing Cory food?

I'm glad your 2 species are doing well for you now.

I do want to chime in on the "correct" temps for fish. Fish kept at too low of their "optimal" temp may be a bit sluggish but maybe live longer; too high & they tend to not live as long but may be more active... & need to eat more...& produce more waste.

Breeding can be influenced by temps too, whether tank bred or wild. Some eggs don't hatch (or much) at the "wrong" temps.

It's less a matter of fish survival, they can live through temp. fluctuations for the most part, but trying to find the "sweet spot" where they act normal & at least attempt to breed if they can. Tank bred fish are less fussy usually than wilds, no need to hit the perfect pH & temp. (been there, lol.) Many of our fish are farmed & more forgiving than most wild caught fish.
 
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