Lighting in Canopy

[Iconz]

I'm getting ready to build the canopy for my 20h. I'm going to install my 4x24 t5 lighting setup into it.

How far off of the water should I have these lights?

Also, should I have 3 or 4 inches above the lights to install fans, or would fans just below the lights do fine?

I had thought that if i put fans above the lights, blowing out it would help some of the rising heat leave the canopy.

Thx,
JD

[RHAPALA]

WELL I'M NOT REALLY SURE ON THIS BUT I'MN TOLD ABOUT 6 INCH ABOVE THE WATER...AND 1 FAN SHOULD DO THE TRICK

[jojo22]

That sounds about right. You may want to consider 2 fans. one pushing fresh air into the canopy and one pulling the old air out!

[Iconz]

Well, can you have too many fans? I ask because I have 10 3" fans that I ordered online (10 were cheaper than 4 due to free shipping and discounted rate when you buy 10 or more). So, I had thought of doing at least one fan on each side below and between each light.

Example:

http://i118.photobucket.com/albums/o101/iconz_reef/canopy.jpg

[jojo22]

I'll buy 2 of them off of you if you want! And I think that is a great idea. I would make oneside pull air in and one side pull air out. Some may say it's overkill but hey if it makes you feel safe go for it. Keep in mind that evaporation will also probably occur faster so maby two on each side would help cut down on that and still make you feel all warm and fuzzy about it!

[Iconz]

bleh, they were only a 1.19 each bud, so just pay shipping, and I can get them to ya.

Hmm, didn't know fans would effect evaporation... Interresting to know.

[jojo22]

Not sure on that but it would stand to reason that the more dry air crossing the top of your tank the more water would evaporate.
Let me know how much shipping is to 44705! Thanks buddy!

[Iconz]

Well, the function of the fans in the first place is heat controll, right? So why not angle the input fans so that they blow slightly up to avoid or at least reduce contact with the water...?

[jojo22]

Might help but the air is still in an enclosed area which would increase the humidity of that area. You are in idea trying to push the hot humid air out and let cold dry air in. I don't see it being a big problem just letting you know that you may need to keep a closer eye on your top offs than some other people. It would also be ideal if you had a sump with an auto top off unit then there would be much less to worry about!

[Iconz]

ya, well i am going to have an ATO anyway with a 5 gal resivoir sp?

[jojo22]

I'd check that twice a week untill you get a feel for how long it lasts and then my friend you will be golden!

[Iconz]

k, thx :)

[dakar]

Actually let me toss my two cents in here, if you can arrange the fans to blows across the ends of the T5's you'd be a little better off. That is the *hot spot* for T5's. If you can get the excess heat off those points your tubes will last longer, and ultimately keep a cooler tank. So say a fan on each side blowing perpendicular to the ends of the tubes, then add one or two into the top of the canopy to pull heat up and out. Heated air as we all know is lighter than cold and will naturally want to rise... give it a path to rise out of the canopy and let physics help to cool your tank.

[Iconz]

hmm, I can't argue with that logic. Thanks bud!

[jojo22]

WOW Dave what a great thought!! If I ever go T5 I will make sure I do that!!!

[Iconz]

K, so my bulbs need to be ABOUT 6" above the water surface, right?

[iVgOnMaD]

If you add a piece of acrylic between the lights and the water, and make it removable so you can service the light fixtures if you need to, you can completely prevent the heat emitted from the lights from heating up your aquarium since the fan will remove any heat build-up before it manages to get through the acrylic.

Just my two cents.

ps. It will also be protected from moisture and you can put the lights closer to the water.

[Iconz]

hmmm... that does sound like a great idea! But, wouldn't that limit the amount of surface/air contact between the water column and the air above the tank some?

[Iconz]

also, dakar, you are saying to have all 8 fans pulling in fresh air and blowing it over both ends of the bulbs, right? Just clarifing. Thx.

[dakar]

I'm not a big fan of having anything over the surface of the water, it hinders gas exchange, effecting your pH and O2 concentration.

The fans I'd have blowing across the bulb ends drawing room air would be best... then a couple exhausting heat through the top.

[Iconz]

k, i'll make it happen. Heh, I'm startin to catch on to some of this stuff, I had thought about the gas exchange problem! haha I'm learning, slowly, but surely! :)

[dakar]

There are other reasons not to use glass or plexi over the tank... but it can get pretty deep... reflection, angle of incidence and all sorts of stuff... Run it bare and if you notice any salt spray on your tubes then it may be time to look at things. Are you using waterproof endcaps?

[Iconz]

yeah, I have them. I haven't even started making the canopy yet, that should be either this week or next.

[iVgOnMaD]

You can add one fan that will blow air between the Acrylic and the water surface and another one on the opposite side to suck the air out. You can attach them to the acrylic itself. It might even help LOWER the temperature of your tank.

The reason I like to add a barrier between the water and the Electrical components is for my safety and my aquarium's safety, and to keep the salt-creep from damaging any of my components. You have a lot of fans, take advantage of them!

Hope this helps with your project.

[Iconz]

Yeah, I'm looking at every option. Thanks for the input, keep it coming!

http://i118.photobucket.com/albums/o101/iconz_reef/canopy2.jpg

Here's a sketchup of my current plan (prior to the barrier idea between the water column and the tubes).

[Iconz]

Alright! More questions!

Heh. I started laying out the wood for the canopy last night. Which, in turn, led me to laying out the lights in the canopy. All of that seems fine. Here's where I ran into an "I don't know":

- Where in the canopy do you place the ballasts? And are they water-proof (for the most part) ? If they are not waterproof, what do you do with them?

[perpetual98]

I generally mount them on the back of the canopy. Keeps them out of the heat and humidity of the canopy and keeps the wires to the bulbs short.

Eric

[dakar]

I'm with Eric, on the back of the canopy, and be sure you have some sort of drip loop in the wire s to/from the ballast... better safe than sorry.

[Iconz]

Gotya! Thanks guys!

[Iconz]

also, the wire you sent me that goes from the lights to the ballasts, eric, is stiff wire. Is there a reason for this? Does it work better than the more flexible stuff?

thx,
JD

[perpetual98]

It's solid wire, instead of stranded. I think you'd find you'd have a hard time trying to stick stranded wire into the ballast plugs, but I've never really tried it.

[Iconz]

yeah, i would, especially withoug soldering (sp?) the ends of it...