cooling for tank with canopy

The strength of the stand is in the larger upright pieces, not the plywood skin which is more to eliminate lateral or side to side movement. The existing hole up high in back is perfectly placed for the exhaust if you were to add a fan blowing in down low on one or both of the sides. Without the fan(s) the humidity inside the stand may be a big problem.

 

The humidity is a concern. I'm also looking at running a light at night for an algae scrubber or macro in the sump. It seems like at least one hole or fan low in the cabinet would be of help. Possibly a low voltage fan would do?

 

I run a light all night over my refugium for the macroalgae and to balance pH. Back when I was using metal halides and VHO's I had the WalMart clip on fan set up over the sump so it blew across the length for coolin gand was controlled at first by a Ranco dual stage temp controller and later by my Reefkeeper Lite. The fan is still there but not needed other than for humidity once in a while when we are also running the evaporative cooler in the house during the shoulder months.

For permanent fans the Vantec Stealths are great, DC powered and low speed so very quiet at only 23 dBa full speed. When you control them with a adjustable DC power supply or wall wart and sllow them down at say 9 volts they can't be heard at all and still provde tons of cooling.
I used two of them in the front door of my old chiller cabinet with the back open and worked great, here is a pic showing the brown grille I installed in the door with the fans behind it.



This was the canopy 10+ years ago when I first installed the MH lighting and fans, if you look closely you can see the equal sized 4" holes in the roof of the canopy for hot air to escape.


This is the same canopy a few years ago after switching to AI Sol Blue LED lighting.

 

Wow. That's alot to think about. Great info ADR. First, it's seems that the cabinet sump area would benefit from ventilation. Second, done right, I may be able to supply all cooling needed from ventilating the cabinet.

 

That is possible but I would still think about venting the canopy, even if you don't have forced air, fans, natural convection helps. It really depends on youl lighting. If it is MH, VHO, T-5 or PC then I would install fans, if it is LED you may not need fans if the wattage is not ridiculous.

 

I really appreciate the help. My main concern was assembling the cabinet/tank before modifying then having to disassemble later to add ventilation. The canopy I can modify later with no problem. Where would be the best place to cut vent holes? I now understand that lower is better for convection, but higher would be more effective for fans.

 

For cooling the enclosure, fans down low, blowing cooler, dryer air in and exit holes up high and as far away from the fan as possible for warm damp air to escape. Convection will work this way even if the fans are not running since the warm air rises, or more accurately the cold er air displaces it and pushes it up.

If you are trying to cool the surface of the water by evaporation then the fans need to be close to the top edge of the tank or sump. If it is in the canopy I would place the fans down low so they blow across the water, if it is over a sump I would use a clip on, clipped on the edge of the sump and angled slighthtly down so it ripples the surface across its longest distance.

I did both of the above. Somewhere I also have photos of clip on fans from WalMart on my sump edge. I still keep a fan over the sump hooked to the temp controller on my RKL controller but it has not run in 2 years unless I plug it in and run it manually to see if it still works.

 

Good luck. I wish I could vent my canopy enough to not overheat my tank in the summer with halides. Mine is open in back, and i tried many fan combinations including the big 6" artic king fans and could not run without a chiller. Without house ac, my house temp gets unbearable because of it as well. I miss my radiums because my LEDs don't have the same growth rate or coloration.

 

Thanks for the input BB. A few questions if you don't mind: 1) what kind of led's are you using now? Do you find you need a chiller running led's? What temp do you keep the house in the summer? I'm not entirely against getting a chiller, but I'd like to exhaust every other possibility first.