Using mirrors to illuminate dark spots....

[roger saltwaters]

Anybody ever try this? I have some dark spots in my tank and thought about putting a mirror outside the glass to light these areas occasionally. Sound crazy?

 

[bif24701]

Many mirrors manufactures use some copper, don't ever let it in the water.

Can you not add some more lights or T5s a LED light bar?

 

[roger saltwaters]

I mean externally. It's kind of a 'cliff' area. Side illumination is the best way

 

[Desmond]

Sounds like a nice experiment why nit give it a try and leave feedback. Essentially though more light to cover the tank would be better. Unless the cliff area will still block the light. I usually put corals that prefer less light in shaded srea from my overhangs. Sun coral being one of them

 

[cracker]

That sounds like a very cool experiment. Let us know how worked out !

 

[Triggreef]

so I have my leds mounted vertical from the sides so theres no shading in the center of the tank, so they shine down like a V. At one point I had also mounted some mirrors in the top center of the tank like at a 45 degree angle to mirror the lost light back into the tank. I have a par meter and there was a significant increase. Like from 100 par without, to 120 par with them.

It got annoying though to have to pull them out every time I worked on the tank. I gave up and installed more light in the middle (on drawer slides so I slide them out of the way) which was much more beneficial.

On the outside of the tank I don't see the benefit. Between loss of light through the glass, and just not that much light going through there in the first place, I don't think you'll see a difference.

 

[Diesel]

Isn't this bending the rules of nature?
We have cliffs on the reef as well but no mirrors to lite them up.

 

[cracker]

I don't know Diesal , Keeping Marine tanks is bending the rules already ! LOL

 

[711reefer]

I would be concerned with hotspots using mirror or even mylar. panda film is much greater at reflecting light. in the indoor horticulture world mirrors are never used. in fact just putting something white on the outside glass would probably reflect light better. I have often thought of painting the outside glass white for better disbursement but have yet to do it. you would also have to keep corraline off the glass for better use of light...

 

[mcarroll]

I have some dark spots in my tank and thought about putting a mirror outside the glass to light these areas occasionally.

What light are you redirecting into the tank – sunlight? Whatever the case, remember the glass is going to filter the light in a not-completely-favorable way.

Isn't this bending the rules of nature?
We have cliffs on the reef as well but no mirrors to lite them up.

Interesting tidbit I ran into the other day: Sunlight loses its directionality below a certain depth – eventually, light no longer appears to be coming from "up". It's just "everywhere".

So depending on the depth of reef the OP is simulating, this might be a legitimate light simulation! ;)

 

[Diesel]

What light are you redirecting into the tank – sunlight? Whatever the case, remember the glass is going to filter the light in a not-completely-favorable way.



Interesting tidbit I ran into the other day: Sunlight loses its directionality below a certain depth – eventually, light no longer appears to be coming from "up". It's just "everywhere".

So depending on the depth of reef the OP is simulating, this might be a legitimate light simulation! ;)

That's interesting, can you share that tidbit you been reading?

 

[mcarroll]

Similarly at depth, you start seeing some red light being generated....radiated from chlorophyl.

Will try to scare up the link....I try to log all these "tidbits" on my blog, BTW.....link in sig.....lots of interesting stuff there already.

 

[mcarroll]

Ocean Optics by Mobley

It's a freeware book that surprisingly few people seem to bring up....still digging into it myself. ;)

You'll like this:
http://www.oceanopticsbook.info/view/light_and_radiometry/visualizing_radiances
(Actually not published on the blog yet....but it's in the pipeline.)

"shows the radiance at a depth of 50 m. Now multiple scattering has removed almost all information about the sun's zenith angle. [...]Chlorophyll fluorescence is now responsible for almost all of the red light"

Showing the "reappearance" of red without the azimuth info...

 

[jcrow802]

I have dark spots on my 75 also and a few cliff areas. I was thinking about adding more light. Would another led light or t5 work better? Is it just a preference thing?

 

[brandon429]

this mirror deflection is key to my pico reef

without it, 1/3 of the bowl would be dark, the part where the brain coral gets light is only because a 4 ft special cut mirror I installed reflects kessil led back onto the vase.

 

[saltyfilmfolks]

Anybody ever try this? I have some dark spots in my tank and thought about putting a mirror outside the glass to light these areas occasionally. Sound crazy?

I'd like to see the tank and the places you're talikng about

 

[brandon429]

here's a snap. this is the old pic before the mirror I don't have update. see the white round spot of light hitting the thin wall behind the vase, that's all dark due to the directional nature of the kessil, which is angled so I don't have shading in front. as soon as a bought a 4"x48" custom mirror cut for 30 dollars the back half is lit perfectly, no shading.