Lighting for a deep 90G Bow at 26"

[SALTMAN1968]

I am considering (read: needing) and upgrade from my T-5 x4 54w Tek lights (216w total). My goal is soft and eventually hard corals.

I see many threads on MH vs. T-5, my suspicion is that my tank will run hot in summer (it did before w/ 75g and same lighting).

My hunch is to go with an 8 x 54w T-5 with individual reflector system 4 10k/4 actinic to avoid overheating (and hopefully avoid needing a chiller).

However, the depth is what concerns me. Generally will MH's penetrate further depth? Is there a rule? OR if I get 432W of T-5 on the tank is that the same as a fixture with 2 x 150MH plus a couple of T-5 fixtures built in?

Also, the tank is a Bow so, I only have 12" to work with (I know... tricky!)

Thanks!

[charlie]

I am considering (read: needing) and upgrade from my T-5 x4 54w Tek lights (216w total). My goal is soft and eventually hard corals.

I see many threads on MH vs. T-5, my suspicion is that my tank will run hot in summer (it did before w/ 75g and same lighting).

My hunch is to go with an 8 x 54w T-5 with individual reflector system 4 10k/4 actinic to avoid overheating (and hopefully avoid needing a chiller).

However, the depth is what concerns me. Generally will MH's penetrate further depth? Is there a rule? OR if I get 432W of T-5 on the tank is that the same as a fixture with 2 x 150MH plus a couple of T-5 fixtures built in?

Also, the tank is a Bow so, I only have 12" to work with (I know... tricky!)

Thanks!

Hey there,


My thinking is you could probably get away with 6 T5 here, the wattage is irrelavent. Not being the T5 expert around here, I think you would be alright with the depth, you could always add a couple of reflectors if you don't think it looks right. Being that you only have 12" to work with, I think 6 is a good option tho. Are you going to have a sandbed? If so, that would cut your depth to 22-24".
Alot also depends what type of "hard corals" you want. You can combat the heat with the use of fans placed either on your tank, or on your sump. HTH

[SALTMAN1968]

Charlie: there is an arag bed of perhaps an inch, so I am only cutting to about 24-25" I was in the LFS and the guy showed me a T-5 set up with 8 bulbs that might fit. I wasnt looking specifically if they had indiv. reflectors will need to confirm!

So, back to my original question then: MH's are just preference for look and color and have no impact on how deep they penetrate vs. T-5's?

With only 324 w T-5 (6 bulb), doesnt that feel a bit on the low side for this tank considering a future of SPS and LPS?

I know, the issue I am going to have is the width of the hood. I may consider ditching the hood (although its a great/clean look).

What about 2 mini-HQ units separated and placed rather central on the top of the tank and then supplement with a single or double T-5 strip?

I dont know why I am trying to convince myself that HQ's are a better light source. Please convince me otherwise!

[charlie]

You are talking to the wrong guy about trying to convince you that T5's are better than MH. In my opinion, you get better penetration with halides. But the T5 is a good light, and alot of folks are having good success with sps and T5, just look around on this site, and you will see that is true.

Like I said tho, ditch the wattage thinking, it is outdated. IMO wattage means nothing, it is all about how much lite you can get to the bottom of the tank, OK?

I will give you a link to Sanjay Yoshi's site where he rates different MH bulbs. As far as I know, he has not tested T5 lites'
Sanjay's Reef Lighting Info Pages

Hope this helps you out a little.

[SALTMAN1968]

Helped me out A LOT!
Thanks a milion Charlie!

[Ratpack]

I believe Posidon will chime in here eventually, but he is running a 90g I believe and only using 5 T5 bulbs and growing SPS on the sandbed. Of course his are overdriven which helps, but I believe you would be fine with the 6 bulb setup you have now, especially if you have the individual reflectors. If anything, you could put the hard corals up near the top of the rock and keep your softies down near the bottom as they will not require that much light. You may even be surprised to find that you can grow some hard corals down near the bottom. I believe T5's have a penetration depth of 24" as their optimal range.