sounds like bad ballasts to me! 20 amps is more than enough (most breakers are only 15 amps) but heres a thought, have you tried firing your ballasts a few minutes apart from eachother to prevent a large surge? also I seen blue world has aquamedic reflux cube ballasts on sale right now for 110.00 Ive had one for 3 years and still going strong bar none the best setup Ive seen yet! built in cooling fan and no restriction to airflow across the windings. check them out you wont be dissapointed. stay away from the A.M. fixtures though had a spacelight pendant and junk is all i can say.
