[slief]

Originally Posted by jonasroman

Is it more with me that need to run these lamps on 100% "high output mode" and still not extremely much light? I have some corals (stylopora pistillate, pink) standing exact below a cluster with this 100% running effect, but still quite dark coral, and my N o P values are not high. I have no PAR meter, so I can not measure, so I wonder if there is some who have measured the PAR? I am not interested in PAR when all channels are in 100% as that is almost never the reality, but the PAR when you run a reasonable ordinary program like 100% on blue, maybe 30% white, not so much green, and maybe 100% on the others, thus a program which looks good and is mimic natural condition for most of us. My believe from start, as I added one unit more than recommended, was that my investment should give me some margins upwards. Maybe I am too critical, and all LED have these limits?, or something else in my tank cause these some dark corals despite so near the cluster? That is the reason why I am seeking PAR measure from some private aquarium so we can compare and learn the best settings. In other aspects I like the light.

/Jonas Roman

You should not ever have to run these lights at 100% in high power mode unless you have your lights way far above the water and or don't have enough lights for your display. On my frag tank, I run the LX7 around 65% and on my main display, I run around 75%. That said, these lights are very strong in the blue spectrum which is very hard to distinguish intensity. It's the white light that makes things look brightter but our corals get most of their usable photosynthetic radiation from 420nm to 460nm which is the blue spectrum. As such, using your eyes to judge intensity won't do you much good. Heck, even a par meter has some trouble in that spectrum. The only I use my PAR meters for is acclimating tanks to new lights.

I suspect your issue is low nutrients and in fact, low nutrient systems typically prefer less PAR than a high nutrient system.If I were you, I'd back the intensity way off. You could bleach your corals.