cooling fans

[grazhopr]

Hi TRT,

This topic has been beat up in many different ways...
I did a search yesterday, but couldn't really tell what can meet my requirements.
Here's the deal.
I have looked locally, but haven't been able to find 4" fans, only 3". I read the Icecaps will deliver ~37 CFM of air. Is this standard for all similar fans?
On the other hand, I read from one of the threads that it is recommended to have all fans blowing in the canopy, not the other way around. this is supposed to be more efficient (???).
Any thoughts about this statement ?
And finally, How many cooling fans are recommended if i can only find 3" fans? I currently have 2 x 175w MHs and 2 x 20w fluorescents. I plan to upgrade the fluorescent to say 96watters and add some MHs in the future. Room temeperature is ussually 80 F. I read the temperature where the water surface will be , and with the lights on: ~86 F.
Any info is appreciated !

Thanks !

[Buzz_Hog]

The best method for using fans is to have the fans on one side blowing in and the ones on the other blowing out...

The ones blowing in will blow cool air into the hood and the ones blowing out will pull the heated air out....

If you have both blowing in, it will create pressure inside the hood and leave no efficient exit for the heated air inside... It would be like having all pumps pumping into the tank with no bulkheads or overflow....

If you have all fans blowing out, it will create a negative pressure area.... Which would be like draining the tank and not giving it any returns...


Know what I mean???

[thefatman]

graz.. any chance they have a radio shack or something similar down there? they sell 4" fans.

[Christofari]

I just recently installed fans into my hood. 2 on one side (60.00 each from aquarium store) 2 on the other side (25.00 each from electronics store. I soon realized why the other fans were so much cheaper, they are about 3 times louder. In about a month or two I'm going to take them out and replace them with more the more expensive quiter kind.

[grazhopr]

Originally posted by thefatman
graz.. any chance they have a radio shack or something similar down there? they sell 4" fans.

There used to be one but it was closed... I don't know why. They sold pretty neat stuff ! . Anyways, I'll check other places. I haven't really looked around much . I think I was just trying to save some bucks. There was this other place with fans twice as expensive.
I also checked and a 4" will blow a lot more than a 3" (twice as much !!!).

Thanks for the push!

[grazhopr]

I may order some icecaps...we'll see!

[grazhopr]

I just found a place where they sell fans in many sizes. They even offered me two 4.7" It sounds like an odd ball.
The prices are very good. I think I may get the big ones.

[Junkzoo]

check into eBay, that's where i got mine,,,5 for $20! new.
or do a search on electrical supplies/electronic/muffin fans etc.
4" is a common size for these,,,just make sure you get 110v,not 12v DC
BTW: my canopy has two fans blowing out ,one on each end , and one blowing in , in the back.

[dotel]

Fans from a computer viewpoint.

We have to use lots of fans in alot of computer equipment that can move massive amount of air. The same applies to tanks. I have two 12cm fans on my MH's Tips on fans.

BALL BEARINGS!!!!!!!!!!!!!!!!!!!

alot of fans are sleave bearings which lead to louder fans, that have a high chance of failure, but also tend to cost quite a bit less.

1 ball bearing ends up quieter with a good lifespan. Costs more

2 ball bearings end up very quiet with good lifespan. costs even more.


I use the permium computer fans for my hood. Might look into them they will require your own 12volt p/s to be hardwired into the fan. these can be purchased at Radioshack or electronics store for usually less then $40 for a good one. That can run 5-10 fans easily.

Fans I use are

EnerMax Uc-12FAB-B 12cm. They also have a reostat for fan speed control. They retail for about $25. But since I work for a company that uses them I get them at cost which is about $8. So I'm sure you can get them for 10-15 on the net, easily.

I run these on LOW. if I run them on high they don't really drop the tank temperature, but will add about a gallon of evaporation a day to my tank.

[Flatfish]

Graz,

Radio Shack has 6" 115vac fans rated at 65cfm for $23 each. They are a little spendy by quite heavy duty and very quiet. I installed two in my hood a week ago to cool my dual 400w/VHO setup. They knowcked off about 5 degrees off the max temp of the tank (which I am embarrased to say was close to 88 degrees F).

Joe

[Stang69]

I buy the el cheapo fans at Walmart that way when they quit I just go spend another 10 as opposed to another 20 or so for the radio Shack or IC brand fans. I buy the simple run of the mill clip on fans 6 inch I believe and clip the on the back of the canopy and have them blow in



Hope this helps

Jeff