
there is no difference whether the light is on or off its the same size, it just keeps encrusting. as far as the zoas they are physically attached to the sponge. cant they be removed from the sponge with out damaging it?
sponges are hard to kill except by air bubbles. I have plenty of sponges in my tank and they are not really "oh my gosh, they are taking over"
I have purple vase, plain white encrusting, a spiky pink encrusting, a soft velveting encrusting and yellow finger. Their growth is limited by food. Since I feed my tank a fixed about per week, their growth is static. Easy to cut and move, just need to physically hold it down somewhere until it sticks.
