View Full Version : Switch from CF to MH

04-15-2007, 08:13 PM
I have a 30G tank with CF's - 65W Actinic 03, 65W 10000K and 130W 6700K.
If i were to switch to MH could i just use a single bulb? Any recommendation for me. I generally have soft corals and a few fish.

04-15-2007, 08:28 PM
One of the things you have to consider when switching to MH lighting is that it generates a lot of heat and you have to manage it as high water temperatures are not conducive to healthy fish or corals. There are a number of ways to do this ranging from chillers to fans to tank placement - so it depends on your circumstances.
Are you planning on moving from softies to SPS and clams/anemones? If not then why switch? CF lighting is just fine for most softies, some LPS and even some clams without any problems.
I have MH lighting over 3 of my tanks and it is a real challenge with the heat. Last summer I lost all of my SPS because I just could not keep on top of it (and a few other catastrophes)

04-15-2007, 08:43 PM
I have real space issues at the top of tank with two coralife fixtures and hang on skimmer and feed for phosban reactor. I was wanting to add a sump with overflow box and put my skimmer on the sump but don't have enough room for the overflow. So to get more space and some extra coral growth i was considering the MH. I agree about the heat issue.
Anyone know of a really small overflow box?

04-16-2007, 04:29 AM
Perhaps you might want to consider HO T5's as an option. They're fantastic and really open up the doors of livestock selection for small tanks (less heat issues).

04-16-2007, 06:14 AM
yeah comparing T5's to MH is like comparing apples to oranges, but in your case T5's would probably be the better option.

04-16-2007, 02:08 PM

I just made the switch from 4-HO T5's , to 250W Metal Halide over my 33G sumpless. I made a canopy that hangs from my ceiling (making sure there was lots of space for the heat to escape) it is currently 10 inches away from the waterline of my tank, but is adjustable. Overheating was a huge concern of mine especially on such a small tank. So I installed two "whisper fans" one on each end. When these fans are on the tank temp. doen't even get as warm as when I had the T5's directly on the tank. As for the corals I've never seen them happier! The switch is possible, it may take more creativity and patience but it's worth it, BIG TIME. Good Luck!

04-16-2007, 07:14 PM
Hey Roman
Do you not loose too much light into the room with the light fixture so high?
Are whisper fans a make of fan?

04-17-2007, 03:24 AM
LOL! You do loose a bit of lighting into the room (not too too much!), but I didn't have lights in my livingroom so it worked out perfect. I plan on building onto my canopy to prevent the light from straying beyond the tank. You'd have to see pics to see what I'm talking about. I'll try to post them tom. morning. I believe whisper is a brand, they make no noise at all, that's what makes them so good, the fans have manufacture dates of like 1979, and 1982. They work well I have no idea where my bro got them from. I just wired a switch onto them and as soon as the water starts warming up I flick them on.