Hood cooling?

[adamfinke]

I'm looking for some quite fans for my hood.
I have 6 T-5 fixtures and my water temp got up to 82.5degs. Picked up 2 4" raidoshack fans and they move some air but to loud. I guess you get what u pay for 10.00ea. Now I have 3 fans hope it's enough. Please let me know what you are using thats quite, pics are nice to for some ideas.

Thanks

 

[AZDesertRat]

In my totally enclosed 60" canopy with 2x250w MH and 2x140w VHO I used two 120mm (4") Vantec Stealth computer fans, one in each end, both blowing in with equal sized holes in the top for heat to escape. The top holes were above the reflectors and towards the center so the cooler dryer air had to travel across the canopy and up to exit. What I found amazing was the canopy self cooled even when the fans were off due to natural convection with no other help.

The fans are 12v DC so I used a variable voltage DC power supply to vary the fan speeds acording to the cooling requirements, faster in summer and slower in winter and shoulder months. The power supply was a "wall wart" type used to charge cell phones etc and is only about $10-$15 at places like WalMart or Frys Electronics. The Vantecs are very quiet at 28 dBa @ 53 CFM each and I found them at Newegg.com for about $14 ea. This gave me about 10 complete air changes a minute when the fans were on high which was plenty. Higher speed fans are louder and the extra velocity really wasn't needed, I tried many different fans and always came back to Vantec Stealths.

 

[adamfinke]

Are you blowing out or in the canopy? Sure would like to see some pictures.
Thanks for the info.

In my totally enclosed 60" canopy with 2x250w MH and 2x140w VHO I used two 120mm (4") Vantec Stealth computer fans, one in each end, both blowing in with equal sized holes in the top for heat to escape. The top holes were above the reflectors and towards the center so the cooler dryer air had to travel across the canopy and up to exit. What I found amazing was the canopy self cooled even when the fans were off due to natural convection with no other help.

The fans are 12v DC so I used a variable voltage DC power supply to vary the fan speeds acording to the cooling requirements, faster in summer and slower in winter and shoulder months. The power supply was a "wall wart" type used to charge cell phones etc and is only about $10-$15 at places like WalMart or Frys Electronics. The Vantecs are very quiet at 28 dBa @ 53 CFM each and I found them at Newegg.com for about $14 ea. This gave me about 10 complete air changes a minute when the fans were on high which was plenty. Higher speed fans are louder and the extra velocity really wasn't needed, I tried many different fans and always came back to Vantec Stealths.

 

[AZDesertRat]

Both fans blow in. Blowing out reduces the life of the fans significantly since the air is damp and they corrode and gum up. Also one in and one out is not productive since the second fan does not add anything, it just moves what the first fan feeds it.

Here is an old pic when I first constructed the canopy about 9 years ago now.

 

[AZDesertRat]

And another more recent one with the new AI Sol Blue LED's installed using T track but showing the fan in each end and the holes in top.

Those are the original two fans from 9 years ago, they have never been replaced and are still like new condition. I remove andclean them maybe twice a year at most just to get the grunge off the blades.

Everything seems happy with the temperatures even before the switch to LED's. The fans along with one clip on fan over the sump allowed me to sell my 1/4HP chiller as it never ran anymore unless I started it manually just to see if it worked. The only downside was the evaporation but an ATO system took care of that and made my life easier!

 

[greg0385]

Plus one on what AZ says, i recently bought 4- 120mm fans from radio shack ($10each), went to walmart and bought a power supply($18) that you can vary the volts(3-12) i wired all four fans(two on both sides) in parrallel. These fans are super quiet and do a awesome job, first time i turned them on i drop 2degrees in a hour at 6volts power.

Thanks to AZ for the help when i was looking to buy pc fans

 

[greg0385]

I'm looking for some quite fans for my hood.
I have 6 T-5 fixtures and my water temp got up to 82.5degs. Picked up 2 4" raidoshack fans and they move some air but to loud. I guess you get what u pay for 10.00ea. Now I have 3 fans hope it's enough. Please let me know what you are using thats quite, pics are nice to for some ideas.

Thanks

the fans i got radio shack are i think 28db and 78cfm, they were by theramltake and were black frame with red fan blades. my tank ran 78F with no high power lights on and my house stays steady 72F. With the fans on i have to use a heater to keep from getting too cool.

 

[cdness]

I have 4 120mm fans and a 12V power supply from the shack to go into my canopy. I have a question though... With an open top canopy, should all 4 fans blow fresh air into the canopy and let the hot air rise out of the canopy or should I do 2 in and 2 out?

All 4 will be mounted into the back lower part of the canopy so the airflow can get under the T-5s.

 

[greg0385]

I have all 4 blowing in with 3-4" holes on top with a open back covered by eggcrate. I think they do a better job blowing in air vs sucking out air

 

[adamfinke]

Great that gives me some ideas for making changes to my hood.

 

[AZDesertRat]

Blowing in. Blowing out sucks hot damp air over the fans and soon ruins them. Plus 2 in and 2 out just gives you the CFM of 2 fans since the other 2 are just moving what the first two feed them.

 

[adamfinke]

Nice canopy, did you build it? I like the all white inside, so you have 4 fans total 2 on top blowing in and the 2 on the sides blowing in?. Awsome!!!

 

[REEFKEEPER10]

I have a lasko blower fan blowing into my canopy. Even at a hundred degrees in the house it keeps my tank at about 78 degrees. Hope this gives you a idea.

 

[AZDesertRat]

No. Two fans total, one in each side as you can see in the pic, both blowing cooler dryer air in. The top is just drilled holes cut with a 4" hole saw so I have the same amout of surface area for the hot aire to exhaust out the top, either by convection or with the fans which can even be run one at a time or together and at 6 different speeds, 12v, 10.5v, 9v, 7.5v or 6v. I find they do not work reliably at less than 6 volts.

I built the stand and canopy myself. The canopy is 1/2" oak plywood reinforced with 1x2 pine where needed and trimmed with solid oak 1x2 and corner moulding on the outside. It has two full width piano hinges so the front can be opened by itself or the whole top can be opened for maintenance. The doors use recessed european hinges and open also.
The stand is 2x4 and 2x6 framed with a solid 1/2" floor which is watertight to hold small leaks if they were to happen and skinned with 1/4" oak plywood and 1x4 solid oak trim. Everything is sealed and white epoxy coated on the interior, canopy and stand, and stained Golden Oak with 5 coats of satin exterior spar varnish to protect it. Its 9 years old now and holding up well.

 

[adamfinke]

WOW Is all I can say it's really a sweet setup. Can't wait for my tank to look as nice as yours. I just need to get rid of the hair alage and get some purple coraline growing and it won't look to bad.