MH Advice

[jesterns2]

I am planning on upgrading my lighting this year. I have a 75g tank and want to have SPS, Clams and an Anenome. What I am most partial to is to hang MH`s from the ceiling. My wife would prefer I build a canopy. Either way what I need to know is should I go 250w halides or 150? Also what brand of lighting (pendants and ballasts) do you folks recommend?

Thanks in advance!

 

[raynist]

I have a 2x250w MH fixture with 2 t5's for sale for $190

It is a maristar fixture, would work great on a 75

 

[Llamaguy]

http://www.reefcentral.com/forums/showthread.php?p=16292003

I remember reading that 24" depth was the cut off for 150w bulbs, but can't find it now. T-5 supplementing could always be added to a canopy if you find yourself needing more light. 175w SE bulbs would also cut the need for UV glass as well if you build a canopy.

 

[jesterns2]

Thanks Llamaguy

 

[cloakerpoked]

At 24" deep, I'd really recommend going with a 250w fixture. It's a lot more common, and honestly, between 2 bulbs you're still only consuming an extra 150w of power. That's a lot, but for that depth, that's what I'd do. I had a 120 and a 72 bowfront (both about 2 feet high) and used 2x250w MH on that setup. I have a 60 cube now and still use 1 250w MH. Although, If I'm not mistaken, the 75g tanks are shorter (like 18" or something) in which case something like a 2x175 combination would be fine.

Unless you want something like a 12" high canopy on your tank, I would not suggest a canopy. If you're set on a canopy, I recommend t-5 lighting. If you want a pendent style, you'd be fine with lights, but there again, you could choose t-5 over MH.

 

[BBoley24]

I agree with cloaker. Many options as well.

 

[brian3]

I agree with cloaker. Many options as well.

They are a wake up though on your electric bill. My 250 watt pull about 350 each at the plug due to the general inefficiencies with ballasts and 3 of them added about $25 per month just running 6 hours a day.

 

[Raceimage]

When I set up my 120, I had 2 - 250watt MH and 4 - 48 inch VHO flourscents over it. I liked the look; however, I was always fighting the heat buildup and my electric bill increased quite a bit. I switched to a TEC 8 lamp T5 fixture. No heat transfer, less electric consumption, and still plenty of light . The only thing I lost was the "shimmering" effect that the MH brought.

 

[cloakerpoked]

The only thing I lost was the "shimmering" effect that the MH brought.

You mean that isn't worth $30 per month?

A 8x48" t-5 lamp is going to cost quite a bit to run, and will also produce a decent amount of heat without some sort of fan. Not at the level of a halide fixture, but then again, with a small fan blowing between halide and the water, you will significantly diminish the temperature transfer to the water.

Bulb replacement in a t-5 fixture can be an expensive proposition (in some cases more than MH), and power isn't so expensive yet that it is prohibitive to go one way or the other. Getting an Electronic ballast for your halide rather than a magnetic will address the inefficiencies mentioned earlier.

In the end, it comes down to what you want. People swear to get better growth/color with both halides or t-5's. My personal take on it is that you get better blue spectrum coverage with t-5's and they will make your colors pop a little more, at the expense of intensity and higher PAR values that you get with a Halide. Halide's also tend to marginalize faster, which is either better if you want lower par value ranges at the edges of the tank for lower light stuff, or worse if you're wanting an even distribution throughout the tank. I'd definitely settle your canopy/no canopy debate first, and then flip a coin if you decide to go with a pendant :spin2:

 

[jesterns2]

Well I'm definitely not going to do a canopy. I am going to get halides and hang them. If for some reason we don't like that look

 

[jesterns2]

We are going to go with hanging pendants to start. I'm going to go with dimmable 250-400w ballasts because we may upgrade to 300g next year may end up needing 400w depending on the tank we choose. I would like to keep clams on the sand so a 250w may not be enough in the event of a large tank.

 

[Jabberwock]

Might be mistaken here, but in my reading it seems that the sand-dwelling clams like Derasa aren't *quite* as light hungry as the ones that like to sit on the rocks (Maxima/Crocea). If you're trying to keep Maxima/Crocea low in a deeper tank on a rock then MH might be the best bet...

 

[jesterns2]

I just used dersa clams as an example, I won't get lights until later in the year and haven't started educating myself on clams lighting requirements other than they need high lighting

 

[jer77]

I used 250W PFO pendants before they went under. They were cheap and used 2 for my 75g. I didn't have problems keeping anything. If you hang them get smaller pendants, compared to the big umbrella like ones, to focus the light. Def get DE bulbs too

 

[jesterns2]

Jer77, why do you suggest DE bulbs?