Hey Aurejasper, welcome to the forum.
Just wondering if you could give a bit more information on the tank such as size, what the actual readings for PH, Ammonia ect are, what substrate you're using, as well as what filtration and heating you've got in there, just helps people narrow it down a bit.
Are the 'crazy' ones rubbing up against anything in the tank or just swimming in the middle?
Mountain minnow and White cloud are the same fish (i could be wrong but i have never heard of separate ones), it's actually white cloud mountain minnow. There are a few color and fin varieties so that may be why it's been sold with different names.
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