ive got 8 in a 300 gal. and initially the tore my plants a new one, even the java fern. oddly the never touched my crypts or java moss. i have since been putting a sheet of nori (dried seaweed for wrapping sushi i believe) in a veggie clip once a day. now all plants are untouched. i also feed once to twice a day with a mixture of cichlid and spirulina pellets. the silver dollars have even done the spawning dance. none of my cichlids can catch them to put the smack down. hands down the best non cichlid ive ever kept.