New tank design with ATS in mind

[worley]

I've built the frame with glass at the bottom, wooden frame siliconed to the glass with metal mirror corner clips to make sure it stays on, and the light fittings for the PL-L style fluorescent bulbs siliconed on to the wooden frame. A mirror is screwed on to the wooden frame so it can be removed to get access to the lights. Then a small hole through the wooden frame with the cables going to the electronic ballasts that are velcroed to the non-mirroed side (top) of the mirror. Lastly, there are a few extra holes in the mirror for hooks to go into the frame so it can be suspended on chains from the underside of the cabinet inside the sump.

Now, the problem...
At the moment, there's 4x36W PL-L bulbs connected to two ballast, the lights, when on for about half an hour make the glass and mirror so hot that it's only just possible to keep your hands on them, and the ballast get a bit hotter than that (they're rated up to 75C).
Cutting holes in the wood is probably not a good idea as splashes from the screen could get in, the only things I can think of are:
[list]1) cut two holes in the mirror and place two fans, one to blow air out, and one to pull air in[list:2nw1ks92]Cons:
a) difficult, and time consuming
b) Requires a power adaptor for the fans
c) More electrical contacts around water
d) More expense
Pros:
a) Likely to cool it well[/list]2) Use longer screws and have some sort of spacers between the wooden frame and the mirror to let air flow natrually over the lamps[list]Cons:
a) Risks splashing directly on the PL-L bulbs/fittings and water collecting inside the frame
b) won't be as cool as a fan solution
Pros:
a) not much expense
b) easy
c) no more cables[/list][/list:u:2nw1ks92]
I'm leaning towards option 2). I could probably rig something up to protect the contacts getting wet and drill a small drain hole in the wooden frame at the lower end (as it's at a 30 degree slope roughly) in case any water does collect.

Any comments or other ideas?

P.S.
I think 140W will actually do for the moment, it's immensely bright, easily enough to light up our entire living room (and then some) and so bright it's hard to look at it.
P.P.S.
I just put it on top of the tank and put the 150W metal halide on, and it's almost exactly as bright, but different colour temp and no halide "shimmer".

[worley]

I guess with a higher colour temp (which always appears brighter), the lights would be maybe slightly brighter than the halide.
Interesting to know that the halides aren't really that much less efficient than the compact fluorescent bulbs.

[SantaMonica]

How about drilled holes, but no fan? Just passive flow. Would work if one hole were higher than the other. You could cover it with window screen to help keep splashes out.

[Aquagold]

One of the most interesting areas in ATS design is the lighting. It never grabbed me like this when I was putting lights over the tank.
I need more time like you guys so I could tinker a bit more..... might have to plan it into my working day...
One question - will the fans 'de-gas' the water or will they help deliver some added CO2?
I used a degassing tower on a Abalone farm I managed.
Would be interesting to see the results before and after.

Rob

[SantaMonica]

Scrubbers add oxygen, and remove C02, from the water.

[worley]

Well I've taken the ballasts off the back of the mirror and they don't get anywhere near as hot now, I've also added some small spacers (about 3-4mm) between the wooden frame and the mirror to let air through, and it does appear to be running slightly cooler now.
I'm going to collect 2x 80cm computer case fans (roughly 20 cubic foot of air/min) tomorrow and hook them up to an old computer power supply and drill two sets of holes in the back of the cabinet where the sump is to blow/extract air, which should keep it cooler.

[kcress]

I just noticed the mirror... If this is a typical glass mirror it is a reflective joke. They reflect only about 45% of the light that hits them... Slightly, (very slightly), better than white paint. They' are "second surface" mirrors which are horrible. On the bright side you look 55% less ugly in the bathroom mirror than you actually are.

What I'm getting at is if the mirror/glass is part of the cooling issue ditch it for a much better reflector, a "first surface" mirror. That's like they use in commercial lighting fixtures or our lighting hoods for that matter. This metal will conduct and dissipate the heat way better. It's called spectral aluminum or aluminum reflector.

[worley]

I've spent about 20 minutes searching in the UK and I can't find anywhere that supplies sheets of spectral aluminium (or aluminum ), I've found a few products that use it in the reflectors for lights, and I've found plain non-polished aluminium sheets. If you know where I could find any (preferably in the uk) or what sorts of places would stock it, that's be helpful =D
Thanks
Tom

[kcress]

I've spent about 20 minutes searching in the UK and I can't find anywhere that supplies sheets of spectral aluminium (or aluminum ), I've found a few products that use it in the reflectors for lights, and I've found plain non-polished aluminium sheets. If you know where I could find any (preferably in the uk) or what sorts of places would stock it, that's be helpful =D
Thanks
Tom

Tom; A common source for spectral Al is solar space lighting parts. You buy an extension tube and use the material. These are often 90++% percent reflective. They are actually kind of shockingly reflective. They will re-define your understanding of reflective. Check at any of your large building supply places. Do you have Home Despots there? Places like that now carry them.

Example:http://www.solatube.com/en/solamaster.htm

Spool down to the "extensions". I don't think they show much more on that page but that's what I'm talking about. You just get an extension and open it at the joint or cut it with tin snips.

[worley]

Tom; A common source for spectral Al is solar space lighting parts. You buy an extension tube and use the material. These are often 90++% percent reflective. They are actually kind of shockingly reflective. They will re-define your understanding of reflective. Check at any of your large building supply places. Do you have Home Despots there? Places like that now carry them.

Despots! :lol: was that an intentional typo? Funny either way
I've got a B&Q (http://www.diy.com - that domain name must have cost them a fortune, or they were massively lucky) and Homebase (http://www.homebase.co.uk) near me.

Example:http://www.solatube.com/en/solamaster.htm
Spool down to the "extensions". I don't think they show much more on that page but that's what I'm talking about. You just get an extension and open it at the joint or cut it with tin snips.

I was hoping for a sheet of the stuff, as the mirror I have is roughly 3ft x 2ft (a bit under)