livinlifeinBKK
5000 Club Member
So I was working with a 30 watt Spectra Aqua Knight + an inexpensive 18 watt light to supplement my 20 gallon and after adding the 18 watt light noticed an increase in coralline and the few corals in the tank seemed happier. However over the past month the coralline cover has decreased and the current corals just aren't thriving. Nothing else has changed besides adding that 18 watt light that is all blue spectrum and has a UV LED or two as well. I noticed last week that the blue LEDs on the 30 Watt looked to be dimming and as it has been over the tank for a long time now. The tank is primarily just to house the fish that I removed from my other nano with SPS since it's only a 10 gallon and they were just outgrowing the tank. (They were babies when I added them.) Now that I have a few LPS in the 20 as well as 2 Porites corals with Christmas Tree Worms I removed the 30 Watt light that was almost certainly emitting far less than 30 watts by now and added another of the same 18 Watt lights. Should I add one more for a total of 54 Watts or should I first just test out the tank with only 2 18 Watt lights and see if there's an increase in coralline again and see how the corals respond first? I wish I could get my hands on a proper Par meter but haven't been able to find anyone who has one. I would like to add more LPS to the tank (I know that even with one more of the same light it still wouldn't be enough for most SPS (yes I know Porites is an SPS but as long as it's not declining I'm ok with that because I primarily bought them for the Christmas Tree Worms). Here's the tank with the 2 18 Watt lights. Should I add another or wait and see. Btw, when I say more LPS I'm meaning Scolys, Lobos, and Acans primarily. Would also like to maybe add an anemone to the tank for the clowns at some point. I'm trying to take depth and total distance from the lights into account. Lastly, it's a very mature tank.
