They won't be true striped dollars (metynnis fasciatus) they would be like $150. At quarter size you would be able to tell they were schromburgki. At the size of a nickle schromburgki would probably still have spots (the fry have a spotted pattern). More than likely they are probably young rubripinnis which have three to four stripes. Which fade once they grow larger. There are a lot going around being sold for prices a little too high for rubripinnis but much too low for fasciatus.