The loach's food is mainly microscopic organisms (plankton, small crustaceans, insects, flat snails and higher plant debris and algae, etc.) and will not eat small fish.
Can be raised together, however, it is best not to be raised together, loach activity is strong, some tropical fish like static, not easy to mix. And part of the ornamental fish belong to carnivorous fish is to loach as bait, so may hurt the loach.
Extended information:
The loach can be mixed with grass carp, bighead carp, bighead carp, nuisance fish and crucian carp, and should not be mixed with cyprinids, carps, blackfish and channel catfish. Blackfish and bluegill can eat loaches. Carp tend to burrow in the mud and stir up the water in the pond, which is not good for the growth of loaches. Channel catfish, like loach, eat the leftover bait of other fish, organic matter in the substrate, benthos, etc. They are the same as loach as "cleaners" in the pond, which may cause food conflicts. Loach and other fish mixed, usually per square meter can put 5 cm long loach species 5.
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