400w flash boil??

[so-smrt]

i am looking for a new MH light. i dont have a chiller (and would rather not have to buy one) i am looking at getting a 400w MH but i am concerned that it may raise the temp too high. i have it mounted in the canopy of my 75g tank about 10'' from the water surface. any thoughts will be great.

[txstateunivreefer]

jl1199 has 2x 400w lumenarcs on his 150. on his tank he has alot of fans pointed at the water's surface so that he can facilatate some water evaporation in order to cool the water off you may want to think about fans if you dont want to buy a chiller. on second thought you better get a top off system too.

[LoneStar]

Yup Chris has the right idea. Fans facing the water for water evaporation would be the best for cooling the tank. If that does not work, then you may want to look into a chiller, or perhaps a window AC unit. And a top off system is a must for evaporative cooling!

Make sure your canopy is 'open' enough to allow the hot/humid air to escape.

But if you do get a chiller, buy one that is rated a little larger than what you need. You do not want to save a few bucks on getting a lower Hp chiller, only to see the thing cycle 40min out of every hour. A good chiller may run only 10min per hour...saving a whole lot of engery and money.

[hobogato]

i have heard of some people using a dorm refrigerator with tubing and making a chiller. they pump the tank water thru a bunch of tubing in the fridge.

are you set on 400 watts? at macna, sanjay's data seemed to show that many of us were over lighting our tanks with 400 watters. not meaning to side track or be argumentative, just thought i would mention it.

[BIGBIRD123]

I agree...

[RayAllen]

I also agree with ACE on this one. I would go 2 250watters

[erikharrison]

I have a 250 mounted at the same distance. I have some acros that are doing very well under it. Since I only have 1, I am looking at getting another (mainly for aesthetics) but I have also been contemplating VHOs to supplement the dark areas. Also, for the cost of two 400watters you could get yourself an Aquactinics VHO setup, like this one here. (http://www.aquariumspecialty.com/catalog/product_info.php?products_id=1088)

I too am going through this debacle, I don't use heaters or a chiller and my 250 heats the water nicely throughout the day. I fear adding another 250 may heat the water a tad too much, but my canopy has two holes in the side begging for some temp controlled icecap fans. I am going to put a heater in this week though since the temp has been dropping. It's either that, or I am going the T5 route.

[Bill S]

Everything I've heard on the dorm fridges is that they don't work too well...

[Texreefer]

I will second what Ace said.. I have gone from 400s t0 250s and my colors have never looked better

[caferacermike]

There are several good reads as to why dorm fridges only work in ones head. The main argument is that polyvinyl tubing is actually an INSULATOR not a conductor. The idea is to shed heat into the fridge this can't happen if the tubing prevents the exchange. If you used copper tubing it would work well, but you can't use copper. There is always titanium, lol. It's only about $10 an inch.

I run 2x 250w 6" above my water on my 75g, in a home built fixture (you'd think it was a factory build) that uses 2x 2" CPU fans and my water never gets above 80F. We haven't even had the A/C on for about the last 10 days. With the power compacts it comes out to about 800w for 8 hours.

[captexas]

I used to run 2 x 400watt halides plus about 220 watts of VHO over my old 75g reef tank. Heat was definately an issue, even with two fans in the canopy. I ended up having to run a chiller.

Even if you downgrade and run 250watt halides, you should still run a fan or two in the canopy. If you have a sump, you can also add a fan in the stand pointing at the water surface in the sump to help cool a little bit.

[so-smrt]

WOW that was more info than i ever thought i would get! i havent settled on a 400w i had a 250w it died. so i neede to replace it and $$ is really tight and i found a 400W ballest for about the same price as the 250w just neede some advice as to if that would be a good idea. thanks for all the help.

[txstateunivreefer]

well on my 100 i run 2x250w mh and 4x 65wpcs so if you got something similar to that you should be in good shape i have all types of coral and they do just fine i have 2x 4" fans in my canopy and im sure i get some more cooling from the trickle evaporation in my wet dry below ( increased surface area of the H20) and my temp stays right at 79 all day and at night fans go off to keep it constant