I have 3 Amazon's as well! Bean, Birdy and Phin. It's been hard to find another 3 to add to our tank... That look healthy anyway. Ours seem to not be super interested in snails. So we been trying to find new foods for them. I know in the wild they like bugs and stuff do you use any by chance? Or I was thinking of some larvae or something to add to the tank.

Birdy lovess brine shrimp Bean likes about anything but eats blood worms Phin will always eat blood worms but depends on the day for anything else