UV light question

[fazgood]

Does anyone have any information as to what effects a 390-395nM UV light would have on coral? Specifically SPS and Zoas? My son and I are setting up a science project and can get LEDs in that range and wondered if this would be fatal to the coral or what effects that might have. Any help would be appreciated.

Faz

 

[RiddleLabs]

Aloha Faz,

UV, in the 390-395nm range, is usuable by zooxanthellae. This range is also known to induce coloration in some corals.

Things get a little complicated - its not just the spectral quality of the 'light' - it's also intensity and dosage. As the old saying goes: All things in moderation.

Dana Riddle
Kailua-Kona, Hawaii

 

[fazgood]

More on the project and intensity question

More on the project and intensity question

My son is doing a science project on the effects of light spectrum on Zoas. We plan to make several identical chambers that have a light source comprised of specific colored LEDs. In order to be as objective as possible all of the light sources (LEDs) need to emit the same intensity. I am not an engineer so I am learning as we go along but it appears we should use the radiometric measurement in mW to measure the power. The LEDs I ordered all have a 30 degree beam angle so that should help with consistency.

On the spec sheet for the blue LED(472nm) it lists Power Dissipation of 120mW. It also has a luminous Intensity of 4600mcd at 20mA but no mention of light output in mW. On the spec sheet for the UV LED (400nm) it lists Power Dissipation of 80mW. However, the light output is rated in Absolute Irradiance of 12mW at 20mA. Spec Sheet links below.

So, with the limited equipment that I have access to I am finding it hard to try to put together an objective way to measure so we have a similar amount of light to each subject. The Lux meter I have seems to be able to read the UV light but it might be reading just the visible blue part. I need to see if I can find the specs on it. I have access to a PAR meter from SEASL but I have not had time to research if that would do what I need it to do. I believe you assisted in the purchase of this meter for the club.

Any further thoughts would be appreciated.

Thanks

Faz

http://www.superbrightleds.com/specs/uv1230_specs.htm

http://www.superbrightleds.com/specs/b4630_specs.htm