tried pikes didn't end up well . i heard pirahna are over-rated (I do like the black ones). I doubt three would work for life, but a long enough time to suite me . If, i do get them, i can get them cheap, because the lfs breeds them every couple monthes, when they aren't busy. Dan (owner) seems to have been having fun by taking the local bred mollies he always gets, and converting them to saltwater.