Tank not cool, Canopy pic, any ideas?

[Anonymous]

The tank is a 58 Oceanic.

Lights are a 250W MH HQI and 2 x95W VHO actinics

The canopy is 36x18x17.

Any ideas on better cooling?
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[Anonymous]

Closed pic
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[oppajer]

i don't know if this is possible but how about some fans on the top of the canopy? since hot air rises, most of the heat would be trapped at the top. you can then have some openings near the bottom of the canopy so cooler air can go in. this is based on cooling systems for computers. A lot of computer modifications involve installing these "blow holes". just a suggestion.

 

[liquid]

Sounds reasonable to me. I would say probably either adding more fans, blow holes, increasing the CFM of your fans, etc would help cool your hood. I went with a completely open backed hood and this has really helped minimize any heat related issues for me. You can see pics at http://www.liquidreef.com/

hth

Shane

 

[Entacmaea]

First off- beautiful cabinetry! Nice hood.

It looks like one fan is blowing in and the other out? I would gander that the one drawing air out of the hood presently would be more effective if switched to blowing in... In general, drawing cool air in and having that air exit is more effective than having a fan draw the hot air out. The salty air will also possibly effect the electronics of your fan more quickly when drawing hot air out. You also might try to reposition the fans so they are in the front top corners of the hood, both blowing past the pendant and then out the back of the hood- this is actually exiting the heated air then...

Do you have a sump? You might want to employ some evaporative cooling, if you aren't already. A fan going accross the surface of your sump, or adding another fan to blow accross the surface of your tank(pointing both you have presently at the water surface might be worth a try as well...) will be more effective than trying to blow cool air at the pendant.

 

[Modo]

Definately turn both fans blowing across the top of the water. Sucking and blowing hot air isn't going to help with the radiant heat much that the bulb and enclosure are producing. So, counter that heat with evaporation from the tank.

I was running a 250w Iwasaki about 10" from the surface of my 29g and maintaining a constant temp of 80F. I did this by using two 4" radio shack computer fans (alot like yours) that were at the same angle and postition as yours, but facing slightly downward towards the water. In the summer I ran both and in the winter I only ran one. The fans actually cooled the water enough that my heater is what maintianed my constant temp. This system also didn't have a sump and live in TX with 100F summers.

My hood is open in the back, but the difference was my bulb wasn't enclosed. But, I don't see this as much of a difference in way of heat. I really think this is the way to go. If you have a sump you might just use the fans on top blowing inward as suggested above to circulate fresh cool air. Then rig a fan or two to use evaporation in the sump for cooling.

NIIIICE hood BTW.

Note: I'm using past tense because I just broke down my 29g for a 90g and moved.

 

[teevee]

my 150 with dual 400w halides over it was hitting 87 degrees until i added two 6" clip-on fans blowing at the water in the sump. now it's staying fairly regular, around 82. we'll see if it holds once it gets hotter outside.

 

[MarkO1]

Rob,
As many have said already, evaporational cooling is much more effective than air exchange in the canopy.
I was running 2 fans in my canopy, one blowing into my reflector, the other drawing out. My tank temp typically ran 10º warmer than the ambient air temp.
Then I relocated one of the fans to blow directly over the water. BIG DIFFERENCE. Tank now runs only 3-4º above air temp.
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[Anonymous]

Thanks guys.

I got to find a way to aim those fans towards the water without wrecking the hood.

When I am home I will use a fan over the sump. I am affraid to leave it running all day in case it falls in the sump.

I guess I got to find a way to get a permanent fan down there as well. The fan I use on the sump is a 6 inch house fan that I rest on the edge of the sump. That plactic clip has broken twice already. The sump is a 20G high and I have the fan blowing staright down on the water surrface. The sump is too small to get the fan to blow across the surface.

Here is a older pic of my sump.

ALso, I am running 4 maxi jets in the tank for circulation which might be causing heat that I want out.
1 Maxi 900
2 Maxi 640
1 Maxi 440

I know a closed loop would work but I have no idea on what pump or how to get flow all over the tank not just across the top of the tank.
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[Anonymous]

I used to run two of those computer fans in my hood. I hated how much noise they made. But I had a 6" hood and really couldn't accomodate much else. I built a taller hood and raised my MH to 8" above the water. Then I replace the computer fans with a single clip on type fan. This fan is much quiter and moves more air than the computer fans. I no linger needed a fan on my sump after this change.

My tank tops out 2-3 degrees higher than the room temperature.

Louey