[unclejed]

Hi roady, you really should be adding Iodine at least once a week (most products say one capfull). The latest advances in lighting (T5) makes watts per gallon almost obsolete. The intensity is the key along with the penitrating power. No, T5s will not work in your current fixture as the buls are about 1/2 the diameter of your T12s so if your don't want to invest in a T5 fixture just replace your bulbs.