Valuable MemberView Badges
R2R Excellence Award
Partner Member 2020
- Sep 10, 2011
- Reaction score
- Dallas, Georgia
There aren't any poor aquarium lights (within reason) but there are many poor applications. Ove the years I personally used RO, HO, VHO T12, T8, and T5 fluorescent lamps. As for metal halides, everything from 175 watt 4300Ks to a 400w lamp rated 50,000K. At the coral farm, we used Iwasaki 400w daylight lamps in pendent fixtures. All achieved good to outstanding results. We even tried a Fusion sulfur lamp where microwaves bombarded a golf ball-size globe that was rotated to keep it from melting. I always wondered what the maximum reading was on the Li-Cor quantum meter I had - this lamp pegged the meter at over 20,000 umicromol/m2/sec - a magnitude greater than sunlight on a clear day. Back then (the late 90's) we thought corals could use as much light as we could give them. WRONG! LOL. Fortunately this lamp was on loan to us, and I tested it and shipped it back. A few years later, a fellow sent me a small LED array using white and red LEDs, and he wondered if there might be an application for aquaria. Frankly, the spectrum was not very appealing but it got me interested and I built some LEDs arrays that could be used underwater and published the results in 2001, if memory serves. Then PFO introduced their Solaris LED lights, and so it went. There would have to be a compelling reason for me not to use LEDs. The tank I have now uses two LED fixtures and I am happy with coral growth and coloration. The problem I see with current LEDs on the market is that they have the potential to make too much light and without a light measuring device it would be quite possible to over-illuminate a tank. Another issue is the programming - in some cases it is too tempting to change spectrum, especially if the 'significant other' doesn't like the way the light makes then carpet appear. LOL - it happens (based on an email I got a few years ago.) Based on some experiments I did, I don't think LED spectra plays much of a part in coral growth, especially if light intensity is high and the coral/zoox has reached photosaturation. However, coral coloration is a different story. Violet light can cause color shifts, yellow can increase the red color of some corals, and so on. In short, LEDs work for me - high output, programmable intensity/spectrum, low energy consumption and heat output.Dana, regarding LED's, you wrote, "....I won't go there," but I wish you would!
After using halides for 20+ years, I would love to be happy with LED's. 7 months ago I set up a new cube (170L) with two G5 XR15's and 30+ SPS frags as an experiment to see if I could make myself like LED's. After 3 months, I was not getting any growth and felt like I was struggling to just keep them alive, which led me to replace the XR15's with a halide/T5 hybrid.
I know I didn't give the XR15's a fair chance because there were so many negative variables: new tank, small tank, 70% artificial rock, first time with LED's and a tin problem so I went back to the halides to eliminate the LED "learning curve" variable. But I am curious to what your experience has been with LED's vs halides in regard to growth rate and coloration (and ignoring cost factors).
I do plan to go back to my XR15's some day, after I have a more "established" tank, or after my house sells and I move and set up my "dream" SPS system.
Thanks for helping!