SolaTubes for reef tanks

[hypernesia]

Thanks Hahn,
I will make sure they are aware that I am aware of a simple solution.
Does that sound right?!!

[hahnmeister]

Pretty much.

[8BALL_99]

Originally posted by JCTewks
and another "lost" thread from my subscriptions

Same issue with me lol Everytime one gets unstuck, I have to re subscribe.

[hobogato]

d'oh.... this thread was one of the reasons i put in tubular skylights and i forgot to post here.

here is what i did.

here is the way i did the tank originally:

front

back

here is what it used to look like inside the "canopy"


now, here is what it looks like

front

back

from above (i have covered the T5 lights with acrylic covers since this pic)


here is a comparison of the lighting in the tank:


here are hourly progression pics on a sunny day - left side is with the actinics off and right side is with them on



i documented some of the changes to the tank so far in this thread and posted installation documentation in my build thread (little red house) thanks to all of you pioneers that helped me improve my tank!!!!

[8BALL_99]

Thanks hobogato for posting Pictures Here also!

[mborn]

Hey hobogato great job! I especially like the bell reflectors you made for the ends of the tubes! Great idea! I went down to Lowes and picked up some plastic planters to make some for my tubes. I hope they direct a little more light in the tank in the morning and late afternoon when the light is mostly reflected down the tubes (as apposed to midday in summer when the sun is overhead and shines mostly straight down the tubes). Also in the winter, when the sun is low in the sky (at least where I live) and the light is mostly reflected, they should come in really handy.

[landy]

Originally posted by juliovideo
Alternatives.......................

http://www.sunlight-direct.com/

-----------------------------------

Anyone looked closely @ this idea? Surly cost would be the downfall. Maybe a scaled down version not met to light an entire warehouse could be feasible. Defiantly a slick solution to solar lighting.

Landy

[SERVO]

IMO an added benefit of this type of setup is the ability to really limit the amount of rock in your main display. You could easily place stags at the bottom and let them fill in the space. I am really excited to see how you pioneers continue to push the envelopes. Around 2004 some guy posed about solatubes but disappeared. I have been fantasizing about this ever since. S(&^ if we can practically eliminate the major cost of lighting and now with such low energy pumps, a super sized tank isn't really that big of a burden.

mborn; where is your picture that you promised in Ace's thread?

I wonder why more public aquariums don't try this out?

[8BALL_99]

Well really most public Aquariums have skylights over their monster tanks. Well I shouldn't say most.. I've been to 3 and all three had skylights over the main tank.. The other thing is most public Aquariums are mostly just fish.. So lighting isn't that big of a factor.

For us though like you said probably 1/3-1/2 of a reefs running cost is the lighting. Maybe even more on some sps tanks with very low wattage pumps. I know when I did the math for my setup on bulb cost and electricity it added up quick.. Not to mention the added heat from the lights needs to be removed either from the tank or the room. Heck or both lol

[hahnmeister]

SERVO, thats what I plan on doing myself actually. The only way I would want to afford a 500g tank is by using skylights and such other 'energy saving' methods. Its not just the electricity, but the fixture and bulb costs as well. I figure its pretty much break even to start, but not having to buy a crate of bulbs every year is a big bonus. I plan on using some arrays of 80 watt T5s to suppliment the blue of the tank as well as 'off-peak' viewing, but the sun will be the major method of lighting the tank. I will oversize the skylight, and then block out more than half of the glass with blue and purple films to provide a more pleasing color... as well as the T5's. If I was unable to do skylights, I would most likely cap myself at say... 300 gallons. Thats just alot of electricity to suck up otherwise.

As for the 500g, I plan on using Tunze Stream pumps of course, and a sump that is as close to the same height as the tank as possible, and a return pump that only does 2000gph most likely. The skimmer, which I have already, will be under 100 watts... so all in all, Im trying to keep the total pump wattage at about 600 watts (Tunzes may be 55 watts a pop, but they alternate max output between 2 pumps, so its more like 80 watts constant per pair), or $525 per year at $.10/kwh. That sounds like alot, but just consider HOW MUCH MORE those who run tanks this size have to spend on lighting then. Also, the tank will be in its own room, so all the heat and humidity will not tax the main house's A/C unless I leave the doors open (in winter though, its a giant heatsink). Since even the most efficient halides are still only 25% efficient (75% of the electricity goes directly to heat), thats a good thousand or so watts of heat that the tank wont generate in summer to tax the A/C, as well as humidity. In winter, the water will absorb the radiant energy of the sun and release it at night into the room... just like a solarium/sunroom with a dark tile floor. So the tank will help pay for itself by contributing to the home's heating. If I can, I will bury a couple water storage containers in the back yard as well and run heat exchanger loops instead of a chiller. On a hot day, all I will need to run is a small pump to run cooled water from the underground storage tanks through titanium pipes in the sump. Likewise, if the pipes were run through the basement or underneath the flooring on the first floor, it could help keep the house warm in winter, or soak up some more of that cool from the concrete in the summer. There is a website out there about how a guy cooled his 500+watt computer system with a water cooling loop and about 30some feet of copper pipe set on top of his garage floor. Thats some good heat exchange!

Pumps are pumps though... a watt of energy is hard to get around... as efficient as you can get, if you still need 1hp of pump to move enough water, you will need 1hp+ of pump... no way around it. The best thing to do it to try to put the least amount of head pressure on the pumps as possible and use flow-biased pumps with large diameter plumbing (or prop pumps for flow). You also dont need to move large volumes through your overflow/sump... beyond a certain point of say... 2x the tank volume per hour, you arent doing much more than just recirculating, and recirculating should be left to low-pressure pumps that dont have to pump against head pressure. If you want to start saving more on pump electricity, then yeah... you are looking at a solar array system... which considering the way things are going for energy, are a very good investment to consider. My father made his own solar array for hot water heating... in the freezing cold of winter, the water from the solar heater gets up to 150 degrees F easily (120+ is what most people consider 'scalding')... and runs forever (as long as there is enough sun out, lol, then the inline heater comes back on). Being able to shut off your hot water heater for 90% of its use is a nice saver. But even PV solar cells are a smart choice. The time is coming when you may no longer fill up at a gas station, but instead recharge your car's batteries at home. Demand for electricity would go up then, and solar panels are getting cheaper and cheaper all the time. Heck, with a car alternator, some batteries, and a controller/inverter, you can hook it up to your own wind turbine and make your own wind-generator for cheap. Ive seen guys DIY 1kW vertical wind generators like this for a few hundred $$$.

Hmm.... I like that project ^^^. If there is enough wind where I move, Im thinking I should make my own wind turbine for what... $1000 at most, and run my pumps for free. A 15' tall vertical turbine in 10 mile winds should do that easily.

The problem with PV Solar Panels right now is that they only harvest maybe 10-15% of the light that hits them... mostly red spectrum. Until they figure out how to make PV's that are more efficient, they are still worth it, but not AS WORTH IT when the higher power density ones come out later and can make 3x the power or more in the same area. One way to capture 100% of the radiation from the sun (even UV and IR) is to focus the light into a small area, like those 'radar dish' collectors mentioned before. The advantage is that by focusing alot of radiation into a small area that can capture it (like pipes painted black) is that you can capture nearly ALL of the radiation from the light. This is just like the solar water heater my father built, but we are aiming for 200+ degrees because then we will run the steam through a turbine generator (a water pump in reverse, sorta). The water itself can regenerate (the steam gets collected/condensed and recycled) and you have a very efficient and effective solar system. The cool thing is that other than the mirrored reflectors/reflectors (which themselves arent that technical), the system is remarkably easy to make. Once again, the only important parts that you MUST buy usually are the power conversion electronics and controls (phase/frequency conversion, furling control, overload protection). And these arent that technical either.

[mborn]

Since I haven’t posted any updates of my solatube tank in a while, I thought I’d post a few pictures showing the general progression of my tank over the past few years. I installed 4 X 14� solatube brand skylights and setup the tank (84�L X 24 �W X 36�H) with no supplemental lighting in March, 2005 (picture #1, 2005). As you can see the tank is somewhat deep and the rock work was low, and the corals were a good distance from the tubes. Admittedly, when I first installed the tubes I didn’t have a good understanding of how light would be emitted by them. I naively thought that they would be like big tubular flashlights shining sunlight straight down into my tank all day long. I soon learned that as the sunlight reflects down the tubes, it comes out of the tubes at different angles as the sun moves across the sky. Also, these angles change over the months as the seasons change and the sun moves from low in the sky in winter to high in the sky in summer. This made it very hard to place corals. I’d place a coral in a nice bright spot that got about 3 or more hours of continual light, then a couple of months later as the sun changed position in the sky, that same spot might only get 1 hour of bright light or very low light for the whole day. It soon became clear that my deep tank with low rock structure wasn’t going to work. So at this point I corrected my mistake and built a shallower tank (84�L X 24 �W X 23�H). I then added tube extenders to drop the tubes closer to the corals (picture #2, 2006). This corrected the problem quite well. The tubes were now close enough to the corals that no matter what angle the light comes out of them, most of it still hits the corals. This had the effect of increasing the overall photoperiod for the corals. As the tank started to mature through 2006/2007, I continued to add a variety of hard corals, soft corals, and gorgonians to put together a nice mixed reef and see how the various types of photosynthetic inverts would do with this lighting. Also, I added 120 watts of actinic T5’s (picture #3, 2007). I mainly did this so the tank wouldn’t be dark when I got home from work. I hated looking at my tank with a flashlight at the end of the day to see how everything did. It also has the added benefit of cutting down a bit on the yellowish look. I also use blue filters on the tubes in the summer to cut down on the overall intensity. This was necessary because the tubes are only 3.5 feet long from roof to tank and at midday in summer, direct unreflected sunlight shines straight down the tubes. To my surprise, I found that in general, the soft corals thrive under the brightest summer light better than the SPS, which for me, seem to prefer a more moderate, even lighting that doesn’t transition to abruptly throughout the day. For the most part the tubes have worked out very well and the corals are growing in nicely (picture #4, 2008).

Picture #1-2005



Picture #2-2006



Picture #3-2007



Picture #4-2008

[hobogato]

very nice mborn!

[JMBoehling]

Bravo MBorn! Looks awesome. I'll post a few of mine when I get back from MACNA XX

Later,

Jim

[mborn]

Thanks you guys!

[preimo]

I wish i would have see this thread earlier

[iCon31]

I just spend a grip on my MH. Now time to start saving up on this solatube.

[Electrobes]

Here's a question for you sun tubes guys/gals:

What's the largest light foot print a 21'' sun tube can make given the corals (Soft only) are under maximum of 6 inches of water?

I've been planning a coral farm for some time and had originally gone with halides but am convinced that the sun tubes/skylights is best.

I prefer sun tubes versus squared skylights but obviously want to go with what works. The reason I ask about the foot print is because at current I am planning on using 300G tubs which are about 6' X 5' rounded. I am still looking into other holding tanks but for now would like to consider my options assuming I will be using the tubs.

Your thoughts?

[mborn]

I’d say ~ 36� of bright light and possibly up to ~ 48� (which would be pushing it IMO) of a less intense light with the tube higher above the tank. If you’re going to go with the tube higher off the water to get a larger coverage, I’d look into making a bell reflector for the end of the tube (like hobogato made for his tubes) to direct as much of the reflected light as possible into the tank. That will help even out the photoperiod for the tank as the sun moves across the sky.

[VegasReefer]

Bell Reflectors at the end of a solatube is purely for decoration.
The usable photons are traveling down the tube, at angles between 0 and 45 degrees anything bouncing of the tubes surface at an angle higher than 45 degrees will be hitting the water surface at an angle of over 45 deg and simply be reflected.
The bell reflectors round shape would work great if the photons somehow made a 180 degree turn just after passing bast the end of the tube.
You can however add a funnel shaped attachment that would have an angle of 30 - 40 degrees that is 1/4th the diameter of the tube ( IE 16 inch tube, 4 inch funnel ) that would redirect 45 - 70 degree photons 15 - 45 degrees back into the tank. I don't know if that would add enough output to be worth the trouble of measuring, cutting and affixing the cones to be worth while. though it might be an interesting project to use to tie multiple cones together.. Maybe I should get the CAD out and figure out how to do that for a 8 x 14" set up for a 120 x 48 x 28 700 gallon I have planed..

If I get a chance in the morning before I go to work, I will draw up what I am talking about, and show how/why it would work.

[mborn]

Perhaps in theory. But I’ve made bell reflectors for my tubes and have had them installed for a couple of weeks and they do increase the overall brightness of the tank, especially in the pre-noon morning hours and later in the after noon when the sun is lower in the sky and not directly overhead. They also have helped even the light out as the day transitions from morning to late afternoon. I’ve had my tubes without reflectors for 3.5 years and I can definitely see the improvement with the reflectors. So in actual application they provide a bit more than just decoration. The effect isn’t hugely dramatic though (i.e. it won’t make the difference between the tubes working or not working), but they are an improvement and worth doing IMO. As to which shape is better, bell or funnel, that’s an interesting question. I think the bell is sort of funnel shaped, albeit a curved funnel, but it might be worth looking at if a straight funnel is better than a curved one. As far as all the light greater than a 45 deg angle reflecting off the water, I assume that would be true if the surface was perfectly flat and smooth, but with all the current in my tank, the surface is constantly rippling and agitated, so I doubt that most of it is just reflecting off. But if it is, maybe some of it is getting caught and reflected back down by the bells.

[8BALL_99]

I ended up not installing my skylight because I found a nice 3" pvc line running right where it needed to go. There just wasn't any way to move it and have it keep the same fall or slope on the line. So I ended up getting 3 14" Sola Tube brand tubes.. They were small enough to fit by the pipe but still sit pretty centered over the tank. I got them installed yesterday. Well more like last night. It took pretty much all day. Here is a couple pics from last night. I lined the top of my upper canopy/light shaft with FRP before I stalled the inside tube and trim.

[salty joe]

What's FRP?

[8BALL_99]

Originally posted by salty joe
What's FRP?

Fiber Reinforced Plastic, Its the same stuff that my entire equipment room is covered with.. Its a plastic wall board thats used in commercial kitchens and bathrooms. Its just to water proof the ceiling. I plan on covering the inside of the upper canopy with it also. Sheetrock and moisture don't go well together

[8BALL_99]

I took some pictures this afternoon around 5. I also checked the par. At the end of the tube I was getting anywhere from 500-800 par. But you move the par meter down 15" or so and it drops to 200 or less. When the light exits the tube it seems to shoot side ways and where else. I think if it was directed down the light output would be much better.

[hahnmeister]

If you get the tubes close to the water surface, that will 'bend' the light downwards more... raising the intensity. Rays that enter the water at 45 degrees from vertical will be at 30 degrees from vertical underwater... the water surface itself acts as a lens. Since the light rays will be closer to vertical underwater, this will concentrate them more, but at such an angle, the glass sides of the tank will also act like reflectors... another bonus.

But considering you are getting close to 200 at 5pm, I wouldnt worry much... you might have much more than you need. What are the readings like at noon?