View Full Version : Just how much intensity should I use for my lights?

09/17/2017, 07:23 AM
I've got Kessil AP700 system on my 48" long tank. They are 15" off the water line of a 20" deep tank. They are currently set to reach 50% intensity at peak around 2pm and run at that intensity until 6pm then begin to drop. I have several fish and three corals-leather, trumpet and frogspawn branched coral. They open up, do their thing, etc. But how do I learn what's too much or not enough? Suggestions?

09/17/2017, 10:43 AM
There is no specific rule for that. That would make it way too easy! You can try to increase the intensity if you like, although none of what you have listed is really a strong light demand coral. I wouldn't go more than a few percentage points at a time, and do that slowly. Increase it a bit, let it go a week or two to see how the corals react, and go from there.

If you start to see bleaching you are probably too high. One of the things many don't understand is that, especially when using LED's, what might not appear to be too bright for us is actually too much for the corals.

FWIW - I use 2 x AI Sol blues over my 120DT. They are set to 45W/65B65RB, with a very short ramp up in the morning and a slightly longer ramp down in the evening, with maximum intensity from 10:30 AM to 10PM. They are ~ 14" above water. My SPS grow like weeds.

09/17/2017, 10:52 AM
I'm keeping a close eye. Its always interesting to see what others say. I plan to keep primarily LPS and soft corals. But I will have one, maybe two sps on the very top of my rock formations later down the road.

09/19/2017, 10:52 AM
I too would like to see what other have to say. I know we need to watch how are coral react and then react in turn. I've got a war coral though that I just can't seem to make happy.

09/20/2017, 04:26 AM
Here's another spin on this topic. My tank is new. bOD 8/29. I'm having a diatom bloom all over my substrate. Man that stuff is ugly! Three things are common food for diatoms-light, phosphate and silicates. Just how much light can I remove from the equation while I get this bloom in check? I was running about a 12 hour light plan. Different intensities over the course of that 12 hours. But still 12 hours. I've reduced that by 6 and added phosgiard yesterday and will have a media reactor up and running with GFO in two days. So hope to be able to get my lights back to normal soon. But I'm the meantime, what can corals get away with?