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#18
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![]() The only reason I commented on the comparison to MH is because it was already being done in this thread with statements like:
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The PAR38 light in the review used 40 degree optics and through the air lit a 7" circle at 200 µmol/sec/m2 at 18" THROUGH THE AIR (repeated for emphasis). The narrower optics would be expected to provide more "punch" than 60 or 80 degree optics. Therefore the usable light for moderately light demanding corals is about a 7" circle fewer than 18" away from the light THROUGH THE AIR (corals would probably have to be even closer due to PAR loss if measured through water). If we assume PAR is lost through the water and need to bring the PAR values up while still using the single light the light would need to moved closer to the tank making the irradiated area even smaller (based on the bell shaped dispersion of light probably closer to a 5" diameter). I understand and appreciate that the 27W O.C ICE CooL.E.D utilizes more LEDs with wider optics than the reviewed 21W PAR38 but until real data are compiled an assumption about superiority is just that - an assumption. PAR values through water depicting spread and intensity at varying depths (similar to that done in the above noted review) would certainly help legitimize this light if indeed it does provide substantially greater PAR with wider coverage than the PAR38 So again, I think the lights are useful for spot lighting small areas probably no larger than a single "large" colony of 7" in diameter with usable PAR. And again, the comparison to MH was already being made and I was simply pointing out that actual data don't support the claims being made. This form factor for LEDs is good for spotlighting small areas. An array of LEDs is certainly a better bet for more typical display sizes. Unfortunately there has been a lot of unsubstantiated hype about LEDs and now that real data are starting to become available broad sweeping claims with comparison to MH need to be tempered. I've been excited to use LEDs and had wanted to buy one of these spotlights about a year ago but decided not to be a guinea pig as an early adopter and wait until real data became available. As it stands now it looks like the best bet for me is something like the AI modules as I don't have the desire to go the DIY route.
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