Review on Accelerate Algae Growth with CaribSea Purple Up, 16-Ounce for Stunning Results by Jessie Wright

That's what it says for purple things on the stones. Guess what. You can use it for LPS and SPS! I do it with the cap. My bird nest loves it! my darling loves it! My clam loves it! I dose it daily and am not concerned about over dosing because of the stock in my aquarium. 4 o'clock and no clouds! I know people who just use this by hooking it up to an automatic dispenser and then sit back and watch something grow! The bottle contains calcium, magnesium and iodine! No deaths, no problems! Follow the instructions! I highly recommend testing the water before dosing more than the recommended amount!** If you are limiting your dose, do so while the lights are on and the corals are active to get the most out of it!** **