im reading that people want to block out the UV coming from their metal halides, yet some people use 1 or 2 UV leds on their DIY led lighting, whats the advantage of the UV, does it make any big difference? if any one could share a 'with' and 'without' UV led, i would be greatful.

Thanks,

Zeadon

I havent heard about blocking uv light, but uv leds are used to promote coral colouring i beleive. Normal leds dont produce uv light so uv leds are used to help that

Yeah, DE Metal Halides are supposed to be covered with some kind of glass (is it tempered?) so that it doesn't let off harmful radiation. I've also wondered why some LED's use UV.

corals have developed the colors they have in order to protect themselves from UV, more UV=more color

I think Evil is hoping to do some testing in relation to UV leds and coral growth/colour. Not sure when it will be done though. I ordered one UV led from Kaidomain a couple of weeks ago, it still hasnt arrived, but I'll see what if any actinic properties it has, but wont be able to say if it helps with coral growth etc.

Ok. It is a common misconception that UV glass blocks all UV from MH. It doesn't. It blocks about 99% of UV-C, which is the most harmfull, about 20% of UV-B, and only about 10% of UV-A.

As for UV LEDs, the cheaper more accessible "UV" LEDs aren't going to be that effective for what we are theorizing their use for. The KD LEDs are 410nm, where we need UV-A LEDs in the 350-390nm range. Sadly, these LEDs are currently silly expensive.

evil with an increase in the uv range is there any health issues associated with exposure or is it harmless.

This is one of the things we are trying to figure out. I'm not sure just yet if some of the UV LEDs I'm testing have similar UV levels as MH. All the LEDs I'm testing are UV-A, so the worst exposure is to the eyes. There are no other issues.

Evil ... what are you using to measure UV from the MH and LED's? A generic web search yields plenty of UV "meters" but your opinion on a decent one would be appreciated ...

what about these:
http://picoaquariums.com/index.php?page=sh...rt&Itemid=1

380-410, thats not quiet wat u specified but it sorta has 1 foot in 1 foot out lol. $18

wat do you think

I have an Ocean Optics USB spectrometer at my disposal. It's way out of the range of the average hobbyist. I have a UV meter, and it's ok for measuring relative intensities, but the spectrometer tells me so much more.

For a basic UV meter, this is what I have

http://www.professionalequipment.com/digit...v-light-meters/

They get crazy expensive beyond that.

BTW, thanks for the package. Can't wait to try it out.


380-410nm is the bin range for that series of LED. They are most likely the 410nm versions, as they are cheaper and easier to produce. LEDs like that won't produce that wide of a spectral range. They are usually only 5nm +/- of the peak.