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I have just setup a 180 gallon tank and am in the process of getting the bugs out. One of the problems I have is heat. The tank has been running about 81-82 degrees with the lights off. Most of this I think is due to the fact that the stand is completely enclosed with the exception of two 2 1/2" holes I cut in the back for cords to enter and exit. You can really feel the heat and humidity when you open the doors of the stand.

I turned the lights on today and ran them for about 6 hours. Lighting consists of three 250W MH and two 140 W VHO's. The temp got up to 85 degrees. The canopy is vented with four 4 1/2" fans, two blowing in and two blowing out. The back of the canopy is completely open for venting.

I need to come up with some way to increase the air movement in the stand to dissipate some of this heat and humidity. I know this will help with the overall tank temp by not allowing the enclosed stand to trap so much heat. I have thought about installing a couple of 4 1/2 " fans in the walls of the stand to blow air out.

Anyone with any other ideas?
 

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I like Chillers.

if the back of the canopy is open then why not pull air out from all four fans instead of two pushing and two pulling.

as for the stand how is it set up can fans be installed with out being seen or do you have a three sided tank. you need to get some air in there. plus it has to lower you O2 exchange. may be a vent on one end and a fan pulling on the other.

the only other solution is a chiller that I see.

Fred
 

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Here is a pic of the stand.



When the doors are closed, it is completely sealed. The back is a solid sheet of wood, i.e the stand is four sided ... not three. I agree, I need to get air in there. Do you think that these



type of fans like I have in the canopy would be enough in the stand. Or do I need bigger, and if I need bigger what kind and where do I find them?
 

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Well, the temp was 82-83 degrees before I turned the lights on today. After turning them on, the temp maxed out at 85 degrees after 6 hours of all three 250W MH and both 140W actinics. Now at the same time, I was programming my Aquacontroller Jr. to turn the lights on and off, as well as control my fans. So for part of this time I only had 1-2 fans going. It wasn't until about 45 mins before the lights went out that I managed to get all four fans programmed and turned on.

Also, I have been watching the temp since I put water in the tank. This past Saturday the temp was 78-80 degrees. The lights have not been on until today and the temp has been slowly increasing daily to 82-83 degrees this morning before I went to work. When I opened the stand this afternoon to do somemore work on the tank, I got a pretty good rush of hot, humid air in the face. I can tell air is not circulating well cause I could really smell my skimmer initially, and the odor disapated over time, as the doors to the stand were left open.

I'm not sure that fans will completely solve the problem, but it does seem like there is poor air flow.
 

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Nice Tank! You could start with PC fans or what ever those are. I think that I would try putting a vent in the door on either side of the tank and the fans pulling the ari to the back of the stand. the only problem with that is you may get salt creep on the walls. What is on the back side of wall that the tank is on?
 

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looks great dr, i would try 4 fans either above the side doors blowing across, or in the back. if you wanna test it, open the side door/doors, and blow a regular house fan through it and see if it lowers.
is that stand DIY?
 

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No, the stand and canopy came from glasscages.com. Well, I shut the lights off at about 10pm last night and left the fans in the hood running for about another hour and a half afterward. I also left all the doors of the stand open overnight. The temp in the main tank at 10pm when the light went off was 85.7 degrees and the temp in the sump was 85.4 degrees, at 7:30 this morning the tank was at 79.2 degrees and the sump was at 78.7 degrees. So in 8 hours I had almost a 6 degree drop in temp.

The plan for today. I took two of the three covers on the tank off. I will let the lights come on again today and go for 6 hours with them going off at 10pm and the fans in the canopy staying on for another hour and a half afterward. I am also going to leave the stand doors open, since the sump temp and tank temp are fairly close, and see what kind of heatup I have today. If it still heats too much, I will add a fan blowing across the stand for tomorrow and repeat the above procedure. If it helps the temp problem then I obviously need to vent the stand and add fans to see if this will still improve the situation with the doors closed. If the temp does not stay improved with the venting and fans, while the doors of the stand are closed, then I will likely need to add a chiller to the system.

If the temp does not improve with the doors open and fan going, then I still need to vent the stand, but will likely need a chiller also.
 

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do you have covers over the tank? if so these should be removed all of the time. if you are worried about critters jumping out, than put eggcrate over the tank instead. covers will keep the heat in.

it would be better to have all of the fans blowing out. that way you are getting the maximum amount of air flow through the canopy/stand. think of it this way. if you have 2 blowing in and 2 blowing out, your total CFM through the stand is only equal to what 2 of the fans are doing since they counter act eachother. if you have all of the fans blowing out than your total CFM is equal to the total of all 4 fans. the partial vacuum caused by the fans will bring in the air needed to cool the tank from the outside.

G~
 

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Geoff,

I have been thinking about reversing the two fans blowing in to blowing out as you suggested and I will be making that change tonight. However, I do not think that all my heat problem is my lights. Yes, they obviously caused the temp spike yesterday, but as I mentioned before, the tank was already sitting at about 82 degrees, for two days, with no lights on. This was with my stand closed, and the last several times I open the doors, I get a rush of heat and humidity out of the stand, with the smell of skimmate, from likley stagnate air.

If you figure that the tank started at 82 degrees, spiked to 85.7 (almost 86) degrees, and is now at 79.2 this morning, the lights are not entirely at fault. If they were, the tank should have gone back to 82 degrees, which is where it had been for 48 hours prior to the lights being turned on.

BUT ... it didn't. It fell to 79.2 degrees, which is almost 3 degrees cooler than it had been for the past two days. The only difference ... I left all the doors of my stand open overnight. Now what I deduce from this, is that leaving the doors open allowed the stand to vent and cool, cooling the sump water, which is why it was at 78.7 degrees this morning.

Does this make sense? Essentially, what I am saying is that I need to flip the two fans in the canopy around so they blow out, take the covers off the top of the tank (which I did last night), and vent the stand. My next question, is how do I effectively vent the stand? Cut vent slots in one side and install one or two lighting fans (like I have pictured above) on the other side to pull hot air out via the fans and allow cooler air outside to come in, the same way we were talking about with the canopy?
 

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I have the same tank and stand, I had to vent my stand as well. The heat would work its way from the bottom of the tank through the sand and acctaully continue to heat the tank for 2 hours after the lights went out. I also opend the top of the canopy up with a 2' hole in the middle. I eventaully removed the top of the canopy and just left 3 braces going accross front to back, and have fans blowing from both sides.The problem though, without a controler, is on cool days, all the fans on timers can cause the tank to cool to much! :agree:
 

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Brad,

What did you do to vent and cool your stand?


Well, the results of todays test are in. After 6 hours of full intensity MH lighting the max temp was ...... drumroll please ..... 79.9 degrees. Thus, I don't think that reversing the two fans blowing in will be needed just yet. What I need to do is vent the stand. Now I need to figure out what to use and how to do it.
 

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Saltwater Mom
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Cut bigger holes in the back and you can mount some of those small fans inside the stand itself.
 

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I am thinking of getting two of these variable speed fans from Hamilton Technology.



The product description says:
ICE CAP 4" FAN THERMAL SENSOR FAN KIT WITH VARIABLE SPEED

This innovative 4" variable speed fan kit (50 - 120 cfm)includes thermal sensor probe to control fan speed. Includes 4" fan, fan cover, heat sensing probe and power cord.

I figure that two, one blowing in and one blowing out might be enough.
 

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Presure is much stronger than vacuum. Blow both fans in. Make sure you have vents for the air to escape. Go to menards and buy some vented oak doors.
 

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I have the same problem with my stand - it's too enclosed in the sump area. I have to leave one of the doors open to vent the sump to keep the temp down. There's almost a 2 degree difference with the door open. I would suggest you make the opening in the back bigger (if it won't affect the structural strength of the stand) or add fans blowing air in. I agree with Jason, it's better to blow air in - outside air is cooler than the air inside your stand so it'll probably cool it more efficiently and you'll be less likely to rust your fan.
 

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three90s&125sump said:
Presure is much stronger than vacuum. Blow both fans in. Make sure you have vents for the air to escape. Go to menards and buy some vented oak doors.
this is where i completely dissagree. :D

a partial vacuum (extremely small i know) is better at cooling than pressurizing the hood/stand. when blowing are in you are actually increasing the pressure in the area. pressure=heat. i know very small, but still. the opposite is true for a vaccum. also when blowing air in you are not lowering the humidity in the area. just adding to it. when blowing out you are pulling the humid air out of the closed area. the lower pressure also allows more evaporation to occur. when blowing air in, you also create hot eddies in the hood/stand. the air can just sit there and get warmer. very hard to get an even flow by blowing air into a closed area.

blowing air is a great way to cool something in an open system. like you sitting at a desk with a desk fan. in a closed system blowing air out is more efficient. look at all of you stereo equipment that has fans on it. they all blow out. look at your computer fans on the computer, the same thing. if blowing in was more efficient in a closed system wouldn't you think that the computer/audio manufacturers would be doing it?

G~
 

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Well, all I greatly appreciate all the help and input. As an update, the final temp after 6 hours of MH lights was 79.9 degees (as I mentioned above). So I decide to the next step of my experiment. I closed all the doors on my stand again. I did this at about 9:30pm after the actinics went off. As of 7:40am this morning the tank temp was 78.4 and the sump temp was 78.0, after 10 hours of the stand being completely closed. When I opened it this morning, I still got that nice rush of hot, humid, skimmate reeking air but the temps were not elevated. In fact they had fallen from the max tank temp of 79.9 I mentioned before.

So now I am confused, I plan to leave the stand closed today and let the tank go through its lighting cycle today and see where the tank temp ends up tonight. Maybe taking the covers off and getting the fans in the canopy all running at the same time will be enough. I think I am still going to buy a couple fans, like the ones I pictured above, and set both of them blowing out to vent the stand. This should at least help the heat, humidity, and smell.
 
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