GSP seem to like medum light, I have them at the bottom of my tank (18" high) and I only have 200w of pc lighting. They even are growing on the tank glass. There is no need to feed them anything. Also I found these are one of the easyest to split up (frag). I just take them out of the tank, rip (or cut if I have too) a dime to a quarter size piece off and glue the back to a rock. Stick it back in and thats it.