Lighting Choice....very confused

[tdapple]

Ok, I'm setting up a 55g reef 36x18x18. I'm trying to figure out what kind of lighting I should get. Here are my needs..

Well one need, I want to be able to add anything I want, but not buy a chiller or have an ugly contraption over my tank(my wife won't let me hang anything)

Obviously MH is the option to go, but I am worried about heat. I have about 10 inches above the tank to work with and keep the light hidden. I have a canopy, but it's a slide in stand so I have the rear of the canopy is open wich will help ventilate. Anyone have experience with a tank of this size and MH?

My other option is going T5. 6x39w t5 fixture. I have been reading and most sites say T5's are great up to 18 inches deep(wich my tank is) And heat output is lower than MH. But in this scenario I run into limiting what I can add...or do I, since I meet the 18" penetration limit?

All in all, this lighting decision has me very confused, and my wallet is in a panic of being emptied. Any advice would be greatly appreciated.

 

[ZooKeeper1]

I'd go with a single 250 watt 20k DE MH pendant. you can hang it over the tank, and heat wont be a problem. you can get an aquamedic with built in fans for less than $300

 

[SnowManSnow]

I have the single bulb 250w Aquamedic pendant and it does NOT have fans. Not to say you couldn't install one. I know people who have tried to hang these in a canopy and they are just too hot. I have mine hung from the ceiling, and it REALLY doesn't look bad at all.

There are lots of retro kits you COULD install in your canopy. IMO 250w wouldn't be enough for your 55g tank. I would recommend a 450w if possible. Also, if you aren't planning on installing any PC bulbs to help with the blue spect. I'd install a 20k, thats what I have and I'm pleased with it. I think the 20k AB has even more blue... if you wanted more.

You WOULD have to deal with heat in the canopy though ... It Being an open back will help a lot.... you can install fans on the sides.. one blowing in and one out..or both out if the back is open (there are differing opinions on this). You can purchase the fans at most places that sell retro kits. Check out www.hellolights.com they will also match any price you can find advertised I think.

All being said...I'd go with MH bulbs if you can over T5.. chances are you'll just end up upgrading to MH soon anyhow (like I did).

Good LUCK Let us know what you decide!

B.

 

[Sugar Magnolia]

I agree with snowmansnow. 250W isn't going to be enough for a 55. I have 250 over my 30. Go with the 450W and some actinic supplement.

The canopy you plan to install this in could be a problem though. The top of the MH fixture runs extremely hot and if you install it flush with the top of the canopy you're setting yourself up for some melting and possible fire hazzard. Even with the ventilation out the back it won't help the heat issue on the top of the fixture. My pendant is hung about 3" below the cross piece that hangs inside my open top, open back canopy and the pendant itself is about 10" above the surface of the water.

 

[Ben1]

If I was doing a 36" 55 I would get 2 x 250 watt DE 14k-20k bulbs. The only other thing I would consider is a 400 watt MH 10k xm with 2 x 75 watt VHO actinics.

 

[Entacmaea]

I am setting up a ~70 gallon- 36x18x25, and am using 2 250 DE pendants (10K)and VHO actinics. I was considering 1 bulb options, but the cross brace was problematic. Does your 55 have a center brace? Even without one, I would be worried that with a single MH bulb, you would not get a wide enough spread for the outer reaches of 36" tank. When I was considering one bulb options, I also tinkered with the idea of having a single 400W bulb on a moving track. Now that would be cool! With a 18" deep tank, you might even get away with 150 DE pendants, since they will be mounted relatively close to the water in your existing hood... but then I would supplement with VHO's...

 

[SnowManSnow]

IMO you could go with a 450w MH at 20k and have plenty of blue spect.

B.

 

[Entacmaea]

Is there a new 450w MH bulb I don't know about?

 

[npaden]

Is there a new 450w MH bulb I don't know about?

Heh, I was thinking the same thing.

tdapple,

Watts = Energy. Energy = Heat. 250W of metal halide lighting = the same heat of 250W of PC or T5 or VHO lighting. The heat is just concentrated over a smaller area because the bulb is smaller.

You could setup a 36" long tank with 1 MH bulb. And on an 18" deep tank 250W would be plenty of light.

With the 36" length you will have some dim spots on the ends of the tank if you only use 1 bulb. This could be good (put lower light corals on the ends of the tank) or it could be bad (can't put clams or SPS on the ends of the tank). It will also be noticeably darker on the ends of the tank and some people like their tank to be uniformly bright throughout the tank for aesthetic purposes. That part of the decision is personal preference.

My 2 cents.

Nathan

 

[ZooKeeper1]

npaden
you said it all. That light really is plenty for that tank. My lfs has it for $285 with fans. For what it's worth a 250 DE can be comperable to a 400 watt SE. That is a very bright light, and can easily spread the 36". There are alot of lower light sps that would do great on the sides, like montiporas for one, a few different colored digi's on one side, and a capricornice on the other, then you have the whole middle of the tank for light loving sps.
And even with the single, but more so with the double you could actually be limited by too much light.

 

[Ben1]

I have never been limited by too much light then again maybe I never had too much. I used to run a 75 with 2 x 400 watt MH and 3 x 110 watt VHO actinics and could keep any coral in this tank I had. Lots of softies, sps, clams.

What would be low light corals that wouldnt adapt right?

 

[ZooKeeper1]

your right, I probably shouldn't have said that. I do have a 175 on a 15 gallon. But in the past I have also burned a few corals, and seen lower light corals move as fast as they can away from the MH's.

 

[npaden]

I have had problems with open brain corals and blastamossa adapting to high light conditions in my tank. IME most soft corals might take a while but will adapt to higher light while some LPS corals just won't. I put my LPS corals on the ends of the tank where there is lower light and they seem to do much better there than in the middle where I get some overlap of my 400w MH.

Remember that reflectors play a very important part in your lighting decision as well. Most of the 250W DE reflectors focus the light very tight and you won't get very good spread unless you raise the light up and then you might not be getting enough light to your corals.

Just trying to add to the confusion.

Nathan

 

[SnowManSnow]

oops.. 400w.. sorry

 

[LA-Lawman]

I am thinking like Ben, I would use the 250de's. 2 of them. then suppl with VHO. I like my pc's but VHO is gonna be next.

sheesh, you could go with 3 250w de's all 20k and call it a day. 8O
but i imagine u have a budget like we all do.

good luck, be sure to post pics.

BTW - FANS and Chiller are a must. I will never do another reef with a chiller. saved my butt numerous times. you never know hen you will have a freak hot day!

 

[ZooKeeper1]

3 - 250's on a three foot long tank. Thats not overkill or anything. LOL

 

[Anonymous]

npaden hit the nail on the head. One 250W MH would be fine for this tank. I would add a chiller before adding a second 250W MH.