SolaTubes for reef tanks

[cwloo]

Jim,

How long is your solar tube ? And the size of your tank ?

[gatohoser]

Ya that sounds like another really strong reason not to remove the polycarbonate then.

Barryhc, don't forget that the tropical sun is much stronger than our northern hemisphere sun anyways though. I don't remember how it works but when you think about water absorbing light its halfs for every certain fraction of the total distance it can travel. So maybe after like 3" its 1/4 of what it is at the surface. And corals can take that directly.

We do agree though. You probably shouldn't take that lens off. I just don't think that the problem is that you would get UV over-radiation.

[JMBoehling]

Originally posted by cwloo
Jim,

How long is your solar tube ? And the size of your tank ?

90 gallons

(02) 10" tubes approximately 10 feet long.

[barryhc]

Originally posted by gatohoser
Ya that sounds like another really strong reason not to remove the polycarbonate then.

Barryhc, don't forget that the tropical sun is much stronger than our northern hemisphere sun anyways though. I don't remember how it works but when you think about water absorbing light its halfs for every certain fraction of the total distance it can travel. So maybe after like 3" its 1/4 of what it is at the surface. And corals can take that directly.

We do agree though. You probably shouldn't take that lens off. I just don't think that the problem is that you would get UV over-radiation.

That depends on the "collection factor" for one thing, and you have to decide if you believe that 2 times the amount of "natural" sunlight can be pumped into the tank with "skylight collectors". I am stating that it can. Sola Tubes can only get about 50% the value "natural sunlight into the tank. If you don't believe this, then that is a point of contention, but elsewise "think about it".

Secondly, water depth "degrades" light penetration through several mechanisms, you are right about that, but it is not degraded by 75% in three inches, 25% in 6 to 12" of depth would be a lot closer.

We will get less light in upper latitudes, because of "photoperiod", and because of "inclination angle". Aside from some reduction that occurs in regard to inclination angle, as a function of how much light "skips off" the atmosphere, the proper collection of light in higher latitudes can be rather effecient. Photoperiod reductions are about 33% VS "summer" in the midnorthern latitudes. Inclination angle losses can be even more severe, IF methods are not utilized to mitigate these losses.

So, probably not much concern with too much UV radiation with Sola tubes only, but watch out for running MH, or Skylight collectors without UV lenses.

Happy Reef Keeping! > barryhc

[gatohoser]

Doing more research again I found that the first 3 sites that I found that UVB only penetrates 12" were incorrect. Its 5m. Big difference. Still unimportant.

[barryhc]

Originally posted by gatohoser
Doing more research again I found that the first 3 sites that I found that UVB only penetrates 12" were incorrect. Its 5m. Big difference. Still unimportant.

That makes a lot more sense, but I don't understand the "unimportant" part. I'm not "picking" with you here, I'm here to learn, but I don't understand that statement. Can you explain or give "links to" why it is "unimportant"?

Thanks > barryhc

[gatohoser]

I think we agree barryhc. I was agreeing with what you said about it not being a problem.

[Fursphere]

This has got to be one fo the best threads on RC.

YEARS of debating and researching, but little to no actual field results.

[hllywd]

Is'nt that a fact?!?!?!

Sort of like a thread for a device to increase gas mileage on a '68 Pontiac to 175 MPG.....

[JMBoehling]

Rome was not built in a day, and neither is my Reef. Pictures and "PROOF" will soon follow. Like a fine wine, "Patience" my friend

Jim

[Lordhelmet]

JMBoehling i am patiently waiting the day.
Your tank has insired me to completely rethink the way we do lighting. When the time is right i will be useing all the free lighting in the world as well.

[OhMatic]

If I wanted to cut a hole in my roof and use sun light to light my tank. (two 4'x4' sections)
What would be a substance to use to cover the holes in my roof and what would be a good thing to cover the walls of the tube to my tank? Would you make the tube round or square?

[hllywd]

For 4x4 holes you'll probably need to consider commercial skylight units of some type, then for a 4x4 hole you need to do some structural framing, insulating and finishing in the roof and ceiling. The round skylights discussed here be they Sola Tube brand, Velux, or some other brand don't need the framing and trial and error engineering if you are diy-ing the entire project.. Sure I think a 16 sq ft hole in the roof will probably let in more light but how much of it can I keep in my 90G tank and still be confident of the integrity of my roof. I think the beauty or these round skylights is the non invasive nature of the installation (the one I have installed now took me ~2 hrs with little mess). Not that you can't diy a 4x4 hole but I think that's a whole construction lesson in itself, not a diy thing unless your wife is cool with wet carpet...

[barryhc]

Lots of people put in skylights after the house is originally built, and most of them don't leak. Don't trust uncle Marvin, if he's missing three fingers from mowing the lawn.

Sola tubes are fine, but they don't bring in enough light to avoid supplementation.

Either one requires you to run a "natural" photoperiod, which is the biggest drawback for me.

Happy Reef Keeping ! > barryhc

[salty joe]

Barry's idea of bending a piece of reflective plastic got me to thinking. Maybe using a piece of flat reflective material set at an angle would direct the sunlight more directly into the aquarium. I know very little about the properties of light, but would placing the reflective panel at 22 1/2 degrees from plumb cause the reflected light to go straight down if the light is coming in at a 45° angle?

Joe

[barryhc]

You're thinking correctly here Joe, the interesting thing is that the "incoming angle" is changing with the seasons.

We might be able to do pretty well with this still, if say, two angles were utilized. I'll try to work up a graphic later today.

> barryhc

[salty joe]

That sounds good Barry.

I was thinking that setting the angle at the optimal point for winter might be best for better consistancy year round.

An adjustable panel would be interesting.

Joe

[hllywd]

Barry, I have no illusions many people retrofit skylights successfully, however when somebody asks "what substance would I use to cover a 4x4 hole in my roof", it's irresponsible not to point out the fact you CANNOT cut a hole and seal a piece of plexiglass on and not expect to severely damage to your $200,000 investment. I've fixed abortions like that where people knew better than the construction industry standards and decided to reinvent the wheel on their own. I also would contest your your claim "most don't leak". There are many cheap and inferior products on the market yet today that are real bastards to seal properly, I've seen 14"x 48" "bubble" skylights with 2" flanges that leave proper flashing to the installer. Ultimately most DIYers resort to roofing sealant in an attempt to seal these units which usually makes things worse. I still believe it is unrealistic for an average DIYer to install a "couple" or even one 4x4 skylight and end up with a SAFE and SECURE structure.
FYI - WHen I speak of DIYers I don't mean it in a bad way, I supervised volunteer construction labor for over 4 years building homes locally for a large national organiation. As an estimate 75 - 80% of the volunteer people claiming competency required immediate supervision to run shingles in a straight line, frame a wall, hang drywall, etc...

I already have a SolaTube of my own installed in our dining room. It provides a lot of light to the area. Do I think I'll be able to get rid of my lights with the two others I have over a 6' tank? NO! If I can offer my organisms some natural sunlight without rebuilding a section of my roof I will. Would I consider an option that has been engineered and tested to get 16 sq ft of light into the same 6' tank? SURE! Maybe I'd build on a sunroom and not worry about it...

I think the whole idea here was a non invasive way to catch some free natural sunlight, not to completely redesign the house.

Good luck.

[barryhc]

hllywd, I would only use a high quality skylight, and I would not expect the installation of the skylight, or the "reflectors-hood" is to be considered any sort of "typical- DIY" installation.

I have never mentioned DIY.

If skylights cannot be installed correctly, whether during new construction, of retrofit, then explain it to the mfg.

>Barry

[BeanAnimal]

hehe "bubble" skylights. I thought those went out with fondue and bell bottoms.

Bean

[hllywd]

Nope. Still in the big box, "home improvement stores".

[hllywd]

Oh... fondue is back in too... A whole chain called the "Melting Pot"

[BeanAnimal]

yeah my brother and a few other couples went to "the melting pot" and the whole deal ended up costing over $100 per person. Thats a lot fo cheese and chocolate. I ate at Mo's in Indy not long ago and spend less than that on a ribeye the size of Rhode Island and a baked tater to match.

Bean

[hllywd]

I don't particularly object to the 100 bucks - just not for fondue tried it... wasn't too impressed...

For 100 beans I better leave with my fill of sushi and tanked on hot saki!!!

[barryhc]

Originally posted by hllywd
I don't particularly object to the 100 bucks - just not for fondue tried it... wasn't too impressed...

For 100 beans I better leave with my fill of sushi and tanked on hot saki!!!

15 years ago, It was the "Fondue Stube", about $35 a pop.

I loved it, and haven't been back since. I got my daughter a "chocolate foutain" for Christmas, I can't wait until "she" fills it up, and gives me "the front row".

I'll take my Ribeye "pink not red" thank you very much ! ! !

> Barry