fan location in canopy

[almarktool]

on a diy retrofit lights in a canopy where should the fans go i have read both in the back one pulling in one pushing out ? is this correct if so are they really that effective since back of canopy is prob only 4 " of the wall? other choice would be left to right but then u get to look at the fans in your nice wood canopy
anyone ?

 

[mr . salty]

Personally.I don't think it really matters too much where the fans go,just so you have them..You could even mount them on the top if you have room.If the back of your canopy is open,then I would aim them both in..

 

[jester]

I am going to have to do a rare thing(for me anyway). and disagree with Mr. Salty. By facing the fans in, you are essentially creating a blow dryer in your canopy. 1 in and 1 out if it's sealed (or close to sealed) and on oppisite sides. If it's open in back both out. You want to pull the warm air out, not blow it around inside.

 

[almarktool]

jester interesting point,
however with the back of the canopy open and 2 fans facing in then u would iin effect be bringing in any room temp air since fans don't push air like ceiling fans do , they are actually on both sides of the tank with the air intake being on the room side and the exhaust being on the inside of the canopy, so the only air that could possibly be getting blown in there would have to be the air from the room side, correct me please if i am wrong

 

[jester]

What about the heated air in side there already? It's not going to flow out in a straight lie. It will swirl aroun and around. If you have them sucking out the heated air, you will pull as much of the warm air as the fans will blow.
If you have them facing in, you will pull the air from the outside into the canopy, and swirling around inside, mixing the warm and cooler air together. Thus not colling you canopy as efficiently as possible

 

[broomer5]

In my opinon, they're called exhaust fans for a reason.
I plan to have two fans mounted on each end of the fixture, each pulling hot/warm air from inside the canopy, and exhausting this air out each end, allowing the ambient room temperature air to be drawn in from the rear opening of the canopy.
I've recently read that bulbs are intended to burn at a given temperature. I want to remove the hot air as Jester said, not try to cool the bulb. Plus I shouldn't have to use those foam air filter inserts to keep the fan blades and rotor clean.

 

[almarktool]

jester & broomer,
Thank-you both
I am starting to see your point now in regards to using them to pull the air out

 

[mr . salty]

Pull the air out,,,or push the air in,,Either way will work if the back of the canopy is open...If you have them aimed IN(as I do) the hot air will flow out the open back as fast as the fans push in the cooler air...If you have them aiming out,the air will enter the opening as fast as the fans evacuate the hot air...I have tried them both ways,and find in my case they tend to work better blowing IN...

 

[steamboat1569]

I agree with Mr. Salty. either way will work. I know of no aquarium, even public ones that are sealed up where no air can circulate. That would prevent gas exchange not to mention blowing the tank apart eventually through gas build up.

 

[broomer5]

Yeah I don't think it really matters all that much whether the fans blow in or blow out - as long as they blow and you have enough airflow to prevent excessive heat build up.
Whatever works

 

[sal t. nutz]

Either way is prob fine. I was just telling you how I had mine set-up, which it 1 in and 1 out and it dropped my temp so fast, I couldn't even beleive it. And that was even with VHO lighting.