Stan and Debbie established and ran a reputable fish collecting business in Hawai'i for 10 years before relocating to Kinston, NC. They now manage the fish department at Animal Jungle pet store.
OK - My Lamps Are Generating UVR. How Do I Get Rid of It?
There are many choices for UV filters and, even better, are widely available and relatively inexpensive. Your local hardware store probably has sheet acrylic material (sold as 'safety' glazing). Any glazing marked as 'UV Protective' will work. Common brand names are Lexan, Lexan Solar and Lucite. Thickness isn't critical (1/8" or 3/32" is fine), but orientation is - some acrylics are coated with UVR-absorbing compounds only on one side (the directions will tell you which). Avoid hardware store window glass - if the glass is green when viewed edge-wise, don't use it (3/16" 'green' window glazing transmits 75% UV-A and 3% UV-B). If in doubt, use the 'UV card' mentioned above to check the material in full sunlight.
What Are the Trade-offs of UVR Shielding?
Expect the acrylic material to attenuate photosynthetic active radiation (PAR) by 6 to 14% (depending upon brand of acrylic). As a general rule, acrylic tends to absorb most energy < 390 nm, but also attenuates violet and blue wavelengths slightly more than other visible wavelengths. This weakening is not apparent to the human eye (mine anyway) and only a meter can gage the weakening effect. Maintenance is a bit higher, since salt spray will have to be cleaned off the shield (but is much easier than scraping dried salts off a metal halide lamp).
Doesn't UVR Promote Coloration in Corals?
There is a lot of work to be done in this area, and some interesting coloration shifts have been noted in corals exposed to UVR. But it has not been determined if the coloration is due to UVR or simply an slight increase in PAR (especially violet and blue wavelengths) due to the lamp's UV shield being removed.
Vivid fluorescent/reflective coral coloration, in many cases, is possible without exposure to UVR.
nickdo 發表於 2013-6-14 17:12
個研究係表示,
1. 400nm~500nm 已經係最重要的 pigment excitation spectrum.
2. UV 可能有作用, 但非 ...
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