I can but it can be hard to differentiate which ones are which, because there are atleast 3 species listed as upside down catfish, not just one. And yes, they top at out at 4 inches not 3 and it still doesn't mean they won't eat fry. The whole genus will consume fry like there is no tomorrow. There are the S. nigriventris, S. contractus and the S. eupterus sold. I don't want to get mixed up with the species and get the ones that get bigger and more aggressive. I'd rather get petricolas at the price, but can't seem to find any locally. I was going for an angelicas, but they aren't common and most can fetch a high price. So, I'll be aiming for atleast 6-10 juvie petricolas.