2x150w MH - Too Much for 33g?

Hello all,

Yet another potential MH convert here. I have an Odyssea D33 corner tank that's about 26 tall by about 30 wide at the widest. I've used the stock PC/CF lighting for about a year now with good results for polyps softies, etc., but now that the tank is pretty nicely established, I'd like to get a little more serious.

I recently acquired a BioCube 14 with a 150w MH modded in, and am blown away by how good it looks, as well as how quickly my corals grow. Well the BioCube is at work, and it's driving me nuts not having the same results at home, so I figured I would mod up my Odyssea with some MH goodness too.

What I am wondering is if two 150w MH bulbs will be too much, or not enough for my 33g corner tank? I am a little worried that by modding them into the stock hood, they'll only be about 3" away from the water at most. I have done a ton of computer cooling, so getting the heat away from the tank shouldn't be too hard with a good fan arrangement, but will the proximity to the water be an issue?

The MH on my BioCube is about 3-4" away and everything seems fine, but I thought I'd see what you all have to say. I have all the parts ready to do the work, but am holding off in case there's any great input to be had here.

Thoughts?

 

with the tank at a height of 26", i would get rid of the hood and put a mini LB with one 400w mh.

 

2x150w MH - Too Much for 33g?


Gosh yes. --- will be well on way to making "Reef Gumbo" :-/

 

yeah ditch the hood, get a wet/dry filter to replace the one in the hood and put a single MH over it otherwise it'll bleach everything in the tank I'd bet

 

Thanks for the feedback guys! This is why I am here asking questions instead of bleaching corals .

I am borrowing the retrofit kit I was looking into from my LFS right now, and yeah, 2x 150w seems insane! The fit alone would be challenging in the small amount of hood space available. As an alternative, would it be best to install a single 150w or two 70w bulbs? Thoughts?

Just to clarify, the hood has no filtration in it. Just 2x 36w PC/CF bulbs.

For filtration, I am running a CPR bakpak2 skimmer/filter. It's got a pre-skimmer box that works as an internal overflow, the skimmer itself and bio-bale crap, and also a post-skimmer box with standard filter padding, a bag of chemi pure and carbon.

Everything has been running well for about a year, and my only issue seems to be a very slight nitrate reading I can't seem to kick. Nothing seems bothered by it, but it's still frustrating when all the other "bad" elements are reading zero.

Anyhow, about the lighting... any further thoughts?

 

I'd do the single 150w if it were me, less maintence and cost at bulb changing time but their are better people to listen to here than me

 

I agree with RG, after 24" 250w MH wouldnt react the bottom. 150w is good for up to 20" 250w up to 24" and 400w after 24"

 

Ok, so penetration/light intensity falloff is more the issue here then? I was just thinking if two 150w bulbs will make for a bleachy meltdown, one 400w would likely have the same effect. But it seems it may not be so simple.

 

Ok, well it's more for my own closure here than anything else, but I took the advice here and decided to go with one MH bulb. Two weekends and a lot of modding later, I managed to get a 150w bulb & reflector, one 36w actinic CF bulb, two moonlight (superfluous) LEDs and a full system of cooling fans installed into the stock Odyssea D33 hood!

The ballasts for all components were moved external to make room for the HQI bulb and also to reduce heat. I know people here have mixed feelings about aquatraders and odyssea, but they're literally 3 blocks from me, so I went over and grabbed a combo ballast box they had for a discount. It was perfectly sized, with cooling fans (and a 12V transformer I grabbed power for my hood fans from) and room for the CF ballast that used to be in the odyssea hood.

To make a long story short, I did a lot of re-wiring and now I have proper power to everything in the hood. I have been easing my corals into the new setup this week, and already I have seen growth in some of the polyps that have seemed more or less dormant for the last year. The light is crazy intense - maybe the curved front has something to do with that?

The only problem is that while the great airflow setup I created is keeping the hood cool to the touch at all times, overall tank temp goes up about 2 degrees in 4-5 hours of use. Maybe I'll have to put a fan or an iceprobe on the open side of the cpr bakpak or something.

Anyhow, I am SOOO glad I listened to you guys and didn't install 2x 150w bulbs! It would have been way too much.

So now for my question:

How much does the color of the HQI bulb matter? I am currently running a 10k, but it's a little white for my taste. How blue would a 15k or 20k be? Is there any reason other than taste and aesthetics to run any particular color vs another? I have my actinic time covered with the CF tube, but was just thinking a more blue HQI would look nice.

Thoughts?

 

Let us see some pics of your handy work...... We love pics......