Heat with two 175W MH.

[jtown]

What would the heat issue be like with 2 175W MH's? Will I have to have fans installed in an enclosed canopy? I hate background noise and would hate to have to install fans in a canopy, but whatever is necessary for the tank.

Another thing ... right now on my 20L, I have 2 55W PC's can I use two actinic PCs for my new 45 Long or should I get VHO's? I'm going to keep the 20L as a refugium so I'll have to have lights for the 20L, but are NO lights suitable for a refugium?

[Johnnyfishkiller]

What size tank are you putting the lights on? How high off the surface of the water?

I have two 175s over my 55 gal, 8 inches off the surface. I have two fans in the hood and no heat problems. IceCap makes a thermostatic fan that only comes on when needed and only blows as hard as needed. I just put two 36 cfm fans from radio shack on mine. The do make a bit of noise, but like I said no heat problems.

I also run a 20 long for the fuge. I run a sorry ***** 18 watt NO tube over it. I should have more but it works. Gotta talk the wife into an RO/DI unit first though.

[jtown]

I planned for a 45 Long. I'm thinking dual 175ers for now ... 250 will give me a price increase and a heat increase.

[dreadhead]

I have 2 175's on a 75 G approximately 7 inches off of the water surface and heat is not an issue at all.

[brideauj]

I have two 250W MH and two 55W PCF bulbs over a 55 with two 4" fans with no problem, at least in winter...

[ChrisC1029]

I have a 400 W MH and 2 175 W MH's in a 4 foot enclosed canopy, with the lights about 10 inches above the water surface. Heat isn't a problem, in fact I still had to add a heater to my sump, and thats with 3 submersible pumps in the sump. But I have a fairly large water volume in the sump and seperate 55 g refugium, 2 fans in the canopy, and the whole system is in my basement where the air temperature stays around 71-72 degrees year round. I have Ice Cap fans and I think they are relatively quiet.

[pyro383]

Well I took a temp probe on my 175 mh laying on a piece of wood running 15min and the air temp 2" off the bulb was 143 and room temp was 67.

[Russ]

Originally posted by pyro383
Well I took a temp probe on my 175 mh laying on a piece of wood running 15min and the air temp 2" off the bulb was 143 and room temp was 67.

That's no big deal. Just keep in mind that it takes a whole heck of a lot more heat energy to raise the temp of one gallon of water by one degree, compared to raising the temp of "one gallon" of air by one degree.