my little brother brought me two clams he dug from the local stream, and he wants me to put them in my tank. theyre pretty big. one is about 5 inches long and the other is about 3 inches long. so what i want to know is what diseases/parasites do they carry, and is there a way i can treat them in a seperate container to rid them of anything they may pass on to my fish? also, they have this black bristley hairlike growth on parts of them. what is this? i have them in a bucket of water right now. if i decide to keep them in a bucket or whatever, do they need substrate, or filtration? what should i feed them?