Sun = |filter| ---- reef ?

[widmer]

I wonder if there exists some sort of filter or tint that can be applied to glass so the sun could shine through it and only (somewhere close to) the right light spectrum would filter through to be directed into your tank. A perfect application for this would be the people who build greenhouses to culture their coral. I'll save my wild sun-harvesting ideas for if anyone can direct me towards this sort of material.

 

[widmer]

Wow, no replies eh? Maybe I should get in touch with the mechanical engineering department here at the U.

I can picture using properly filtered sunlight to very substantially cut down on electrical and bulb replacement costs by supplementing the filtered sun on days when its sunny, which is the majority of the week depending on your location. The implications for this could be huge for anything from the modest 75g sps with a couple 400w lamps on up...

It was a pretty hot topic that we were discussing a few years back at the overgrow.com forums before they got shut down by the US government (you can read more on wikipedia.com) to harvest and channel sunlight for vegetation indoors. If no one has input here, though, I guess that's ok.

 

[swsmr]

what you need is a Remnant -UV Stable-Greenhouse Plastic Cover, this is what they use on greenhouses but i'm not sure if it will work on fish tanks,

 

[BusterDog]

The only filter found in nature would be water depth.
Would you really need any type of filter?

 

[mborn]

I use solotube skylights to light my tank and in the summer when the sun shines directly down the tubes it’s too intense for some of my corals so I use roscolux # 61 Mist blue filter sheets (http://www.rosco.com/us/filters/roscolux.asp) to filter the sunlight. The filters let in all the blue light and some of the higher spectrum light as well. It gives the tank an overall 10,000k appearance. Rosco has many different filters for what ever spectrum you’re interested in.

As mentioned I only use the filters in the summer when the sun is high in the sky and shines directly down the tubes. I take the filters off in the winter when the sun is lower in the sky and the sunlight is reflected down the tubes as the intensity is lower and the filters aren’t needed.

 

[widmer]

mborn

Perfect, that's what I was looking for. I think I might order some to play with, even though I've just got a little aquarium. Any idea of what the price range might be for just a few square feet to work with?

 

[mborn]

I’ve been getting 20” X 24” sheets for $ 6.95 per sheet in my area. Type in your zip code under the “where to buy” button on the Rosco web site to find distributors in your area. I assume the pricing will be similar.

 

[DrBCool]

Been looking at a sun tube skylight to light my tank .
Everyone says that I will have a serious algae issue .
Do you have an over abundance of algae growth using your solar tube ?
Do you like the tube for lighting the tank ?
Do the corals seem to like the sun in the tank ?

Hey just thought I would share this link so you can check out this guys large Bowl tank lit with a tube
http://www.reefsanctuary.com/forums/new-frontiers/14710-natural-sunlight-tanks.html

 

[mborn]

I haven’t had enhanced or problematic algae growth compared to my previous metal halide systems. IME nutrient control/export and a good clean up crew is the key to keeping algae under control.

Yes, I like the tubes for lighting the tank. There was a bit of a learning curve though. I had to tweak the tubes and the tank initially to get the tubes closer to the corals to get a photoperiod that lasts the length of the day. This is because the light emits from the tubes at slight angles, not straight down, because the light mostly reflects down the tubes. The only exception is a few months in summer when the sun is directly overhead that it emits straight down the tubes.

Do the corals seem to like the sun in the tank? Not any more or less than the bright metal halide systems I’ve used in the past. In 3 years of using sunlight via solatubes I haven’t observed anything special. No enhanced growth/color or polyp extension over the metal halide systems I’ve used in the past. It’s just another lighting option for a reef tank. I get good healthy growth. The same as with any properly setup lighting system. The main benefits have been a lower power bill and not worrying about getting the “perfect” bulb combination. The sun comes up-the sun goes down. I don’t even think about lighting anymore.

If anything the light is somewhat “yellowish” so if you’re going to or have spent a lot of money on “limited edition” SPS frags you should stick with an artificial lighting system with higher Kelvin bulbs to get the best visual effect.