Thanks KJ. Any idea on what type? I'm getting conflicting reviews on if they're neutral or bad for the tank as well. Tank is only a month old and im still new to all this. Also, I dont know if this helps at all but, it does sway a little in the current. Not much but it definitely moves with the water flow. I also don't see a tube or anything that its coming out of. Its like its growing straight from the rock. Maybe found a small crevice i cant see??