What sizw MH to use

[mchammer]

I am setting up a 120 gallon in wall tank. The dimensions are 48" x 24" x 24", it will be all SPS and claims. I would like to know what size MH lights I should use (150W or 250W).

 

[sirreal63]

I would go with 250's, the variety of bulb choices is better. If you go with 150's, use 10K bulbs with a true M81 ballast.

 

[fishcraze_1]

Since it will be all sps, definitely 250's

 

[HaroldT]

+1

I would go with 2 x 250 watt metal halides for a tank of that size if you want to keep SPS.

 

[mchammer]

would the adjustable ballast be ok to use (i.e. 250 or 400)? What kind and K value bulb would be best to use?

 

[shifty51008]

a dimming ballast will be fine to use. as for k value stick to 10-20k bulbs 10k will giver you better growth and 20k will give you better color. I run reeflux 12k and they give me good growth and color.

 

[andrewey]

I would do 2 250's at 12-14k, and if you don't like the look, supplement with some blue leds/t5s. If you don't care so much about crazy growth, go 20k MH.

 

[dwa_jeff]

+1 on the 250w. There are tons of bulb choices and it will give the punch to give you decent par on the sandbed. I am running a 250w 12k reeflux on a pfo m80 ballast.

Another option for a tank that size would be 2x175w halides with iwasaki 15k bulbs. Awesome color and just as much par as the 250s.

 

[oklahoma11]

I used 2-250 watt MH mounted about 8 inches off the water. that should be fine.

 

[dgmanny]

I use Phoenix 250W 14k, which have a great color and shimmer.

 

[mchammer]

Thank you for the replies. I just want to make sure and have the most amount of light and still keep the tank cool without having to use a chiller. Since my tank is in the wall I built a small room around it (just enough space to enclose equipment and water tanks. I did install a bathroom fan that exhaust to the outside, for humidity.

 

[r-balljunkie]

2 x 250, supplemented with something else for actinics is a good reliable setup.

i never liked 150W bulbs....very dim.