More ideas for cooling the MH lighting would be very welocom

[C J Rodders]

I have a 5 tube lighting system that I am about to update with a 250 watt MH unit. The unit should arrive in a week or two. in the mean time, I want to prepare the tank and surrounding environment to accommodate the heat of the MH unit. To date, I have installed an air vent in the wall next to the tank that has direct access to the outside. I have installed two computer 12v fans that sit on a glass shelf just above water level. They are of some benefit but I really don't think they will keep the water temperature down in the summer months. I cannot afford an expensive cooling system and I really don't want to have a huge fan whizzing round all the time. So, what ideas do you have that will ensure I can keep the water temperature at a stable level?
With thanks,
CJ

 

[reefland]

Some larger fans might do the tick over computer fans. Honeywell and Holmes both make small 8 inch to 10 inch fans that can be wall mounted. These work great for blowing down on the top of hoods or mounted under the stand for blowing into the sump.

Venting to the outside is a great idea. Keeping the heat out of the room is the main challenge. If you can do that then evaporative cooling becomes very practical.

 

[fishguru]

Also for clarification, you do not want to cool the bulb itself or you will affect the spectrum. the heat is what creates the spectrum 6500, 10k etc. If you directly cool the bulb it will shift the spectrum (not sure which way) What you need to a solution to, is how to remove the new excess heat from the canopy. My solution was I have a timer that is on my MH, into the timer is plugged in a 3 Outlet plug. One for the MH and one for a Standard House Fan. When the MH comes on, so does the fan, drawing Air out of the canopy. Hope this gives you some ideas-Guru

 

[Pman]

Not to stray from the subject but do you have any data or proof to backup the color shift from cooling a metal halide bulb? Just curious because I recently changed my canopy setup so that the fan blew along the bulb to cool it rather than pulling heat off the bulb which I think causes the premature failure of fans due to the high heat.

 

[StirCrazy]

Not to stray from the subject but do you have any data or proof to backup the color shift from cooling a metal halide bulb? Just curious because I recently changed my canopy setup so that the fan blew along the bulb to cool it rather than pulling heat off the bulb which I think causes the premature failure of fans due to the high heat.

ya there were tests done to show this..
it is in one of the two online mags, when I remember which one I will post it LOL, direct cooling on the bulb lowers the Kelvin value.

Steve