By what do you mean trading fish around? like moving from tank to tank to tank or trading them to fish shops? The answer to both is no, not really. I just don't really feel/want to pay 50 dollars for a gold-nugget :-/ Besides, i don't have any room for the babies. My severums are about the sizes of half dollars now, the smaller of the trio is a little larger than a quarter. My lima is about 6-7 inches long and is getting cramped in his 10 gallon. :-/ He needs to come down into the 45 with the severums.