I second the use of an ATS. Its so efficient that it nearly killed off my chaeto. Both were on the same lighting schedule, 18 hours a day, using two separate PAR 38 bulbs, each with 450nm and 650nm LEDs. Now the bulb lighting my ATS is turned on for half of the original duration. Nitrates and phosphates are undetectable by salifert, API and Red Sea test kits haha gotta be certain. But my Xenias have suffered. Not sure if its because of the nutrients since everything else is doing fine.