We used 6500K "Day Light" Iwasaki metal halide lamps at the coral farm I managed at the late 90's with good success. Since some wavelengths (blue. green, red) are all important in promoting coral photosynthesis, it boils down to light intensity. If your PAR levels are less than, say, 500 micromole/m2/sec, you're probably in good shape in *many* cases.
Yes, you are correct rods, not cones. Thanks for the correction! I see you're in Woodstock, not that far away.
Until recently I thought you were still in Hawaii until I saw Dallas Ga under your name. I grew up in Cedartown and, back in the 70’s, my family would drive through Dallas when we would go to ATL.
Yeah, I hear that a lot. There are a lot of things that attract people to Hawaii. The weather is beautiful almost every day. The ocean is as blue and clear as it can get. But, after living there for 18 years, sunny and 80 every day got to be so boring, and I longed for seasons' changes. The house was on the ocean and I could count Yellow Tangs on the reef in front of the house (if I felt like counting into the thousands.) But salt spray from the waves (sometimes 15-20 footers) takes an incredible toll on a house. And the threat of a major tsunami was always there, every little earthquake (frequent on an island moving northward at the rate of a few inches per year) could cause a small one. And I won't mention the cost of living... In short, Hawaii is a great place to visit but you don't want to live there. I grew up in Cobb County, just to the east of Dallas, so I knew what I was getting into. The house we had built backs up to the Pickett's Mill Battlefield Park, and we love to sit on the back deck and enjoy the beauty of a temperate rainforest. The lab in the day basement is finally large enough to house the tanks and equipment, and I can get some astounding corals I could only dream of while in Kona. All in all, I'll take Dallas GA any day. But if I long for a taste of aloha, Delta is ready when I am, and friends would welcome us back.
If the light intensity is high enough to saturate photosynthesis (200-300 micromole/m2/sec as a very general rule - there are exceptions!) you *might* get away with it. Do you have a compelling reason for such a short photoperiod? 8-10 hours would be much better!
