Help with lighting, MH related. (1 Viewer)

[Aggie05]

I am thinking about setting up a 20 long nano with two 70 watt MHs. I was planning on using the home depot work lights as housings and putting them inside a hood with some fans. My question is how high off the water do I need to have them? I'm hoping I won't have to have an outrageously tall hood on the tank.

 

[KrAs]

Question, why are you going with MH on a 12.75" deep tank? Wouldn't T-5's be an easier choice, any kind enclosed hood will drive the heat into the upper 80's without a chiller. I was running 2 250's on a 55 with a 20 gallon sump and fans in the hood, and I could just keep it at 83, I had one fan fail and it was 87 by the time I got home that afternoon.

 

[aggie4231]

why dont you try a coralife 150w hang on tank fixture. it's metal halide, you can go the route without the hood and you can keep it 6-9 inch from the water.

 

[toefu]

i was thinking of doing the same thing a couple of years ago. 70 watt halides are only good for <15" which is perfect for a 20 long. they don't generate much heat for a 20 and the shimmer is great.

To answer your question, A 20 long is basically (2) 10 gallon tanks, and I used to have a 70watt about 5-6 inches from the surface of the water(from bulb to water).

 

[Aggie05]

thanks, toefu.

To answer the other questions. I was going to use 20K bulbs so I don't think it is going to be overkill. I currently run two 24" VHOs on a 15 gallon so I'm not worried too much. I was going to use two bulbs because the tank is 30" long, so with a single pendant you are looking at severe drop off at the edges. Heat is really the only thing I'm worried about but if they don't put off as much as other halides then I may be ok. If not, ill just go back to VHOs.

 

[melev]

Make sure you do use the glass shield between the 70w bulbs and the water. UV must be filtered away to protect your livestock.