I don't recommend sponges as a major tank feature. I had some, red, yellow, and blue for 2 years, before a house move and an accidental rock-cooking event---the tank couldn't be installed for 5 days, pending some parts arriving, and the whole timetable for a one day smooth-as-silk move didn't go well at that point. The sponges came in with the live rock in the tank's first incarnation, and they went in the move, along with the shrooms, the colonista snails, and my four big bristleworms. The ones I had generally preferred shadowed areas, and grew quite nicely without much intervention. The blue venous stuff I'm not sure was a sponge, but it was certainly interesting, and went over several rocks in full mh light. The rest were cryptic, but interesting bits of color.
Most of the softies I have kept tended to be happily low light, back in a 1980's-90's tank setup prior to these two, and I am interested to know that they tolerate brighter light. Oddly enough, my hitchhiker discosomas thrived in mh light, right atop the rock. Which only proves that discosomas can survive a nuclear strike---these ones (including the sponges) survived a fullblown 4 week cycle on my first setup, so they had already been through the mill.