SolaTubes for reef tanks

[Groove]

Hi SAT,
I don't expect your project to be done, but would love an update. I thought about doing this before I bought my IceCap. I posted this thought to another forum (nameless...) and was shot down for my crazy idea. I hate the thought of spending $1,000 on lights to only have to replace bulbs and pay that electric bill every month.

Thanks

 

[SAT]

Groove,

There's not a lot of progress to report yet except the tubes are now extended their full length. The tank is scheduled to go in on June 14, but it will probably be a month before I can consider putting any water in it.

The construction crew thinks the tubes are awesome. Underneath is always the brightest part of the house, even early in the morning when they show up. There's an illusion that there's more light under the tubes than outside. By comparison, direct sunlight coming through the low-E windows is quite dull.

The color varies quite a bit according to the weather. On clear days it's a "sunny" yellow. On cloudy days it's more blue/grey. Both are kind of wierd indoors.

 

[EdKruzel]

SAT,
Just curious why the reflective dish is not in the top dome.

On the tubes I set up there was a reflective dish nearly half as large as the dome attached inside. The dish was mounted to point south which enables it to extend the photoperiod morning and early evening when the sun is lowest.

Was this option available?

Thanks,

Ed

 

[SAT]

Ed,

Yes, I think a reflector option is available. I may add them later. Since the tubes are lined up north-south, there was some concern that a reflector on one tube would shadow another.

My understanding is the reflector makes little difference in the spring & summer, but can significantly boost the light during the low-angle months in the fall and winter.

 

[SAT]

Ed,

Do you have a picture of the reflector on your tubes?

Thanks,

 

[EdKruzel]

SAT,
Sorry, but I don't have any pics. The tubes are unfortunetly not on my tanks.
My personal tanks are situated in the house so that the tubes would have to go through the center of my master bedroom.
(Wife would kill me)

In early '96 I set-up a tank for a friend and recommended three tubes. He went with three 21'' tubes over his 300gal.

This was the only lighting used and his corals thrived and reproduced.
The coralline was incredible.

This tank was broken down recently and the owner sold the house and moved to florida.

I intend on using these tubes when I build my next home. The tank will be poured concrete and its dimensions will be 20'L x 6'W x 5'H, one foot deep DSB and the natural light. I can't wait...

Ed

 

[JL9210]

SAT,

You mentioned earlier that the tubes would be completed on 6/14. Just trying to get an update and any pictures during throughout the day would be highly appreciated. How's the moonlight absorption?

John.

 

[SAT]

John,

The aquarium installation was put off a couple of weeks, partly because the installer wasn't ready and partly because my builder really doesn't want it to show up yet. Drywall is just going in this week.

The tubes themselves are installed. Pictures probably won't be meaningful until the tank is running, which won't be for a few more months.

The light quality is "interesting". On cloudy days, I get uniform bluish light spread underneath the tubes. It's much brighter than you might expect, perhaps because it's catching light from all directions.

When it's sunny, there are several different effects. The round tubes tend to focus light so there are "hot lines" that resemble what waves produce, except they move much much slower. The combination with surface waves should be interesting. Also, most of the light exits the tube at the same angle it entered. At noon, most of the light is headed down, so I get a bright round spot, slightly larger than the tube, right under it. At other times, I get a big bright circle spread across the room, with a much less intense area inside it. I'll have to put reflectors around the top of the tank to direct that light into the aquarium instead of the room.

I havn't seen moonlight yet, but I expect it to have the right color and the right intensity relationship to sunlight (I have yet to hear of a moon lamp that isn't at least 1000X brighter than natural moonlight). And of course I don't need a timer. I think the moon will be good for biological cycles, but don't expect it to be much good for viewing.

 

[JL9210]

SAT,

Sounds exciting. I just wish I had an example to look at before making any purchasing decisions. I definately want to head in that direction for lighting. I currently have placed a 25 gallon reef setup in my greenhouse. Temperature control might be an issue. We'll have to see.

Thanks for the quick response. Looking forward to your updates in the months to come.

One last quick question... I've heard the 21'' solatubes can put out close to 3000 watts during June at noon. Sounds a bit intense for those corals? Ever think about bleaching effects? Or is that not possible? MH lights often have that effect, could directed sunlight cause a problem like that as well?

Something to think about... why hasn't anyone invented some sort of magnifying glass that absorbs sunlight and targets it? Shouldn't it be relatively simple to design? Cheap to produce?

Hmm...

Anybody get any leads on the fiber optics end? This thread lost that momentum a few pages back...

John.

 

[SAT]

John,

Bear in mind that the "3000 Watts" refers to incandescent lighting. That's equivalent to under 1000W of MH or fluorescent.

The tubes can't deliver more light than hits them. The tank has a 16 square feet surface area and the tubes have a total of about 8 square feet, so the maximum average intensity is 1/2 of sunlight. Assuming loss of 1/2 the light through the tubes, we're down to about 25%. I think that should be safe, particularly since the seasonal changes will be very gradual.

I think the tube output may indeed be more intense than typical MH lamps during short periods of the day (I think the "3000 Watt" figure is averaged over a number of hours and doesn't account for the focusing effect of the round tubes), but I think most animals can tolerate short periods of intense light.

There are a few advantages over MH besides the lack of electricity. One is I get a lot less heat. The manufacturer claims there's hardly any, although I think some infrared gets through. So much for needing evaporative cooling. Another advantage is the light is moving through the day, so I shouldn't get constant hot spots. I think one of the problems with MH is it doesn't move, so some close locations get baked and the corals only receive light from one or two directions, none of which is natural.

Another difference is the sunlight is from a very distant source, so the inverse square law doesn't have much effect within the confines of the tank. The bottom of the tank should be lit almost as intensely as the upper parts, as long as it's not shaded. That may or may not be good, depending on what you're trying to do.

 

[eddie]

sat
fwiw my mh does move (on a star trac hydroponic light mover)
love the solar tubes
i saw some cheap ones for barns and have thought of using some over a prop tank in my barn

 

[scot]

eddie,
Do you have a link for those barn solar tubes?

 

[Krusk]

very interesting topic

very interesting topic

took me quite some time to finished from the beginning.

SAT and Ed

please keep us posted, when you have updated on your project.

This is beatiful.

 

[eddie]

scot
ill find the link and post it

 

[scot]

Thanks Eddie,
I've been looking into DIYing Solar Tubes, but if I can find a well constructed kit at a decent price that would be the way to go.

All the kits I've found around here use plastic flanges on the roof. I really don't think that's going to last.

 

[eddie]

dont think this was the link for barns but they are very cheap
this link was posted by a reefer on this board before this treadsolarbright.com/Prices.htm
the barn ones were only like $90
ill keep looking and find them

 

[eddie]

that link was posted by Rica in advanced topics a few months before this one i think
his tread was called
using sun for natural lighting
the hyperlink doesnt work for me on this tread but it does on his
i try to type it all
http://www.solarbright.com/Prices.htm
btw these use galvinized flanges

 

[eddie]

jl9210 a guy in raliegh nc told me richard harker had a fiber optic lit tank in raleigh
i havent seen it though

 

[scot]

Eddie,
Thanks for the link.

Those tubes are only 10" in diameter and $269. I could get 12" tube kit for $169 @ Lowes, & 14" tube kits for $249, but they all use plastic flanges.

 

[eddie]

i wish i could find the link for the barn tubes
someone posted the link for the company that carried them but i dont know where yet