True UV light and corals - who wants to try?

[Cencalfishguy56]

 

 

RC has a thread by a company in Australia that grow out frags under natural sunlight. The colors look great. They get about 2400 PAR they said.

http://www.reefcentral.com/forums/showthread.php?t=2500838

Pacific east aquaculture has grow out tanks that use sunlight, I've seen a home reef tank that uses natural sunlight also

[tibbsy07]

Sunlight has everything in it - good and not useful. Sunlight is the epitome of light energy. Coral use it in the wild - they'll use it in aquaculture. The local aquaculturing place here has coral greenhouses, where they use sunlight to grow their coral. That's all.

[DNK]

Anything with mercury in it (MH, T5, PC) will have a spike at 365nm, even after UV glass.

Yes, you right. But to achieving noticeable result, we should use a significant amount of ~380nm radiation, as I wrote above. Can you please indicate amount of UVA radiation under this lamps?

[jedimasterben]

It says right there that UV blocking pigments are clear, not that they're the reason behind that bright color.

[Cencalfishguy56]

Sunlight has everything in it - good and not useful. Sunlight is the epitome of light energy. Coral use it in the wild - they'll use it in aquaculture. The local aquaculturing place here has coral greenhouses, where they use sunlight to grow their coral. That's all.

I think it's the best light to use, some corals don't pop though

[evilc66]

Yes, you right. But to achieving noticeable result, we should use a significant amount of ~380nm radiation, as I wrote above. Can you please indicate amount of UVA radiation under this lamps?

I don't have any hard numbers, as it varies from one lamp to the next, but if you look up spectral plots for various lamps, you can see the relative irradiance. It may take a while to find some spectral plots, as many that you will see are clipped to 400nm and above.

It says right there that UV blocking pigments are clear, not that they're the reason behind that bright color.

Clear may not mean colorless though (translucent may have been the more appropriate word). The use of the word "pigment" would have me believe that there is color involved.

[DNK]

I don't have any hard numbers

Thank you. I would like to emphasize again - not enough amount of UVA radiation can't give noticeable result. When using LEDs I know exact amount of UVA, with other light source - can not know. This is an important point.

[jedimasterben]

Clear may not mean colorless though (translucent may have been the more appropriate word). The use of the word "pigment" would have me believe that there is color involved.

From reading from Dana Riddle he says that MAA are clear, but I do know that some pigments do reflect more light than others, but not specifically UV - mostly higher blue and green.

[DNK]

Please don't confuse about different types of UV radiation. UVB and UVC is really dangerous for corals and he protected from them by special proteins, mostly transparent or colorless. But "soft" UVA will a differ in actions on corals.

[metrokat]

It says right there that UV blocking pigments are clear, not that they're the reason behind that bright color.

 

Have you ever wondered why well-lit corals (such as those found in shallow reefs) exhibit such bright, pastel, translucent colors? Science may have an intriguing answer for us.

 

http://www.advancedaquarist.com/blog/coral-skeleton-serves-as-a-built-in-reflectors-and-uv-protection

[metrokat]

More reading

 

What the Malaysian observer had noticed in the Coral-List post was that stressed corals can put on a dazzling neon display of underlying accessory pigments just prior to bleaching. The casual observer might have no clue that this technicolor display is actually a stress condition. In fact, it’s been my own experience that recreational divers often perceive the typical healthy golden-brown or tan color of stony corals as being “unhealthy!”

So, is vivid coloration of some reef-building corals an early warning sign of an imminent bleaching event right around the corner?

The answer seems to be maybe.

In a controlled aquarium study conducted by D’Angelo et. al., several reef coral species were found to concentrate both fluorescent and non-fluorescent proteins (proteins responsible for the neon colors) when exposed to an increase in light intensity and elevated sea surface temperatures associated with bleaching events. In field observation from the Great Barrier Reef and the Red Sea, the authors observed an increased fluorescence/color in the sun-side (upper branch sides) of many Acropora coral species. This vivid coloration was especially pronounced on the upper surface of table Acropora coral colonies.

http://deepseanews.com/2010/09/color-me-stressed/

[jedimasterben]

Have you ever wondered why well-lit corals (such as those found in shallow reefs) exhibit such bright, pastel, translucent colors? Science may have an intriguing answer for us.

 

http://www.advancedaquarist.com/blog/coral-skeleton-serves-as-a-built-in-reflectors-and-uv-protection

The quote in the Advanced Aquarist article has nothing to do with the research article it links to, and Leonard Ho should have NOT written the stub like that. The actual article in PLoS ONE studies how corals that grow on top of other, dead corals (so just the aragonite skeleton) have less UV radiation reflected back onto them.

[metrokat]

The quote in the Advanced Aquarist article has nothing to do with the research article it links to, and Leonard Ho should have NOT written the stub like that. The actual article in PLoS ONE studies how corals that grow on top of other, dead corals (so just the aragonite skeleton) have less UV radiation reflected back onto them.

Do I care? Does a bear shit in the woods?

[jedimasterben]

Do I care? Does a bear shit in the woods?

Considering that you posted the link to back up your statement, yes.

[metrokat]

Considering that you posted the link to back up your statement, yes.

not talking to you

[disaster999]

How much would internationally shipping be? I hope its not some ridiculous 20-30 bucks to ship a few 20mm star LED.

 

Im looking to replace the discolored lenses on my 430nm hyper violet LED from LEDgroupBuy and can only buy 4 of these to fit within my build without overloading my drivers.

[hypostatic]

 

RC has a thread by a company in Australia that grow out frags under natural sunlight. The colors look great. They get about 2400 PAR they said.

http://www.reefcentral.com/forums/showthread.php?t=2500838

 

I've said it once and I'll say it again; I've noticed that my photosynthetic corals look happiest and expand the most when sunlight is shining into the tank. I don't know how much UV gets through the glass (i think almost none?), but there's obviously something in there that they like. Also mammals love sunlight:

 

 

It says right there that UV blocking pigments are clear, not that they're the reason behind that bright color.

 

ehhhh technically I don't know if anything that would be called a "pigment" could be clear/transparent....

 

I think that certain fluorescent proteins (FPs) in corals can act as "sunscreen" protecting them from harmful from harmful short wavelengths of light, and I do believe there is research backing this up (see this nature article).

[DNK]

How much would internationally shipping be? I hope its not some ridiculous 20-30 bucks to ship a few 20mm star LED.

Usually, minimum shipping to USA is about USD15, delivery time is 5-10 working days. However, we can send by cheap Chinese post. Delivery time will be 10-25 working days, but this way of sending will very cheap - is about USD2.

[Cencalfishguy56]

 

I've said it once and I'll say it again; I've noticed that my photosynthetic corals look happiest and expand the most when sunlight is shining into the tank. I don't know how much UV gets through the glass (i think almost none?), but there's obviously something in there that they like. Also mammals love sunlight:

 

 

 

ehhhh technically I don't know if anything that would be called a "pigment" could be clear/transparent....

 

I think that certain fluorescent proteins (FPs) in corals can act as "sunscreen" protecting them from harmful from harmful short wavelengths of light, and I do believe there is research backing this up (see this nature article).

Makes me want to do a natural sun lit reef

This video is cool

[jedimasterben]

 

I've said it once and I'll say it again; I've noticed that my photosynthetic corals look happiest and expand the most when sunlight is shining into the tank. I don't know how much UV gets through the glass (i think almost none?), but there's obviously something in there that they like. Also mammals love sunlight:

 

 

 

ehhhh technically I don't know if anything that would be called a "pigment" could be clear/transparent....

 

I think that certain fluorescent proteins (FPs) in corals can act as "sunscreen" protecting them from harmful from harmful short wavelengths of light, and I do believe there is research backing this up (see this nature article).

Yes, fluorescent proteins help with reflecting excess light but the bulk of corals' protection comes from the xanthophyll cycle (which takes blue/green light and converts it to heat to protect it), especially in these shallow-growing species that have no fluorescent proteins. Dana Riddle sums up all of that in his articles, they're a much longer read

[khuzdul]

I might be interested to try. Is there any experimental protocol for this beyond get the lights and put it over a tank? Is there any standardization of the tanks, feeding, filtration, etc? Standardization of coral type, blocking other light sources? Is there a randomization procedure? Just trying to understand if I can have a tank that is suitable to participate.

[tibbsy07]

I might be interested to try. Is there any experimental protocol for this beyond get the lights and put it over a tank? Is there any standardization of the tanks, feeding, filtration, etc? Standardization of coral type, blocking other light sources? Is there a randomization procedure? Just trying to understand if I can have a tank that is suitable to participate.

My understanding from my question previously is that the answer to your questions is "no." It is simply a visual check. Did it look like your corals were happier? Yes? Great it worked. No? It didn't.

 

I've said it once and I'll say it again; I've noticed that my photosynthetic corals look happiest and expand the most when sunlight is shining into the tank. I don't know how much UV gets through the glass (i think almost none?), but there's obviously something in there that they like. Also mammals love sunlight

Sunlight is amazing. Talk about energy and power. So many things require it, photosynthetic or not. If I could run a totally sunlit tank i would - there are ways to reduce algae that would allow for a sunlit tank.

[hypostatic]

Yes, fluorescent proteins help with reflecting excess light but the bulk of corals' protection comes from the xanthophyll cycle (which takes blue/green light and converts it to heat to protect it), especially in these shallow-growing species that have no fluorescent proteins. Dana Riddle sums up all of that in his articles, they're a much longer read

 

hmmm.... aren't xanthophylls only in the zooxanthellae? To my knowledge it should only be part of the light stress reaction in plants (and algaes).

 

FPs protect the tissues of the corals themselves. If you have access to the nature article you should really check it out

[Nightstar]

Usually "burning" of the lens is not itself lens problem at all, it is a problem of seller, that sold a cheap 350mA LEDs at price of relative costly 700mA LEDs.

I'm going to call BS on this bit. The acrylic lenses on my 405nm and 430nm browned with a drive current of 225mA. Silicone is definitely an improvement though.

Some 380nm diodes might be interesting along with some 660nm for shallow water specimens. I'll wait and see what sort of experiences others report.

[disaster999]

I dont think LEDgroupBuy is sells "cheap" LEDs. Its probably the nature of the UV and silicone that, over time, will just oxidize or burn the lens, whatever material its made of.