Freshwater Clams??

we have freshwater clams in our local river that are 6 to 9 inches. they can get alot bigger than one inch. I know because when I was younger I used to catch clams from the river then turn them loose. my mother has 2 in her pond.
 
They're difficult, but not impossible to keep fed in an indoor situation. And if you're going to do the work of maintaining them you'd be crazy not to get the imo best benefit of keeping them, which would be keeping and breeding Bitterling with them.
 
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