We just purchased a very nice new 120 gallon tank, and are trying to decide as to what lighting we should use. The dimensions are 4x2x2, and would like to grow sps, lps, and clams. We would like to get metal halides but the problem is, I only have 8.25" of room in the canopy, and need to have glass tops in order to keep the cats out. How bad would the heat buildup be? That is why I was thinking of getting t-5s instead. How many bulbs will I need? And wich t-5 bulbs should I get? Any help and recommendations will be appreciated. Thanks
Help with 120 light selection
- Thread starter mraafat
- Start date
mystikdragon7
New member
I would think you can still get metal halides for your tank. I have two 175w metal halides and two 96w vho's that are about 8 inches above the tank. I installed two computer fans and one small desktop fan under the canopy and it keeps the temp down a lot. For you I would get 250w metal halides for your tank.
Sindjin
New member
I have 2 250w MH's over my 120. I ended up making my own canopy and buying a retrofit light kit with the MH's and 2 110w VHO Supplements. My Kights are about 10" off the surface. In addition, I have 2 4" fans pulling air into the canopy and 2 vents up on top. My temp hardly moves even with the halides on.
You should do halides. In addition, you may want to consider a custom canopy to get them a bit higher off the surface.
You should do halides. In addition, you may want to consider a custom canopy to get them a bit higher off the surface.
integlikewhoa
New member
BINGO!! Same here with my 120. Went back and forth and ended up making a new canopy 18" tall and put 2 250w HQI 14K in there. The pendants are hanging from a chain inside and can move then up and down as needed. I also have 2 55w Pc's mounted and have 2 more I need to mount in there (actinics). The tank originally had the 4 55w pc's only in a low canopy which I scraped. The ballast are mounted to the back of the canopy and the timers are mounted to the side. So the whole canopy is self contained except 2 power wires for the timers. I still need to add fans. (too lazy and its winter now plus I have a chiller) It does get very hot in there and raise the tank temp about 2-3 degrees when the lights come on. A fan should take care of that. And you shouldn't need a cover over the tank when you have the canopy on and closed. It should work out good. If you have an open back canopy like I do then put up some mesh or eggcrate to keep the cats out.
I wouldn't try MH's with a glass cover over your tank. You will create a greenhouse effect. A chiller might be the only thing that would keep the temp down with a glass top on the tank. Why would you need them if you have a canopy? If you get rid of them you could go with some fans like the others recommended. The glass top is also going to effect your light penetration and gas exchange as well.
ratherbediving
New member
I agree that halides are nice... but if the original poster doesn't want to modify or make a new canopy, then the question would be-- can you have a 250 watt or 175 watt double ended metal halide above that tank?
I'd want to know how far the bulb would be over that glass top. Is there any chance the glass top could crack if it is too close?
I would think that after you finish mounting the metal halides fixtures the bulb will be closer than 8" to the top of the tank.
If you decide to not go with metal halides, I think you could still get away with a t5 setup and keep whatever you want. I would investigate using two 48" four bulb T-5 retrofits that use the icecap 660 ballast (and parabolic reflectors.) You can get them at www.reefgeek.com. Each bulb will produce 85 watts of light (instead of 54 watts) and should provide more than enough illumination. You might want to buy just one retrofit kit in the beginning and see if you like it; if you don't, you could always buy some halides, and use the T5s as supplementation (perhaps allowing you to get by with 175 or 150 watt halides instead of 250 watt halides) down the road. Until your tank is filled up, you could get by with SPS and light loving clams near the middle/ top of the tank, and LPS near the bottom and be just fine with a 4 bulb setup.
I'd want to know how far the bulb would be over that glass top. Is there any chance the glass top could crack if it is too close?
I would think that after you finish mounting the metal halides fixtures the bulb will be closer than 8" to the top of the tank.
If you decide to not go with metal halides, I think you could still get away with a t5 setup and keep whatever you want. I would investigate using two 48" four bulb T-5 retrofits that use the icecap 660 ballast (and parabolic reflectors.) You can get them at www.reefgeek.com. Each bulb will produce 85 watts of light (instead of 54 watts) and should provide more than enough illumination. You might want to buy just one retrofit kit in the beginning and see if you like it; if you don't, you could always buy some halides, and use the T5s as supplementation (perhaps allowing you to get by with 175 or 150 watt halides instead of 250 watt halides) down the road. Until your tank is filled up, you could get by with SPS and light loving clams near the middle/ top of the tank, and LPS near the bottom and be just fine with a 4 bulb setup.
wetWolger
New member
I think you will be fine, just install a couple fans. On my 120 I have 2x250watt MH and 2x95watt VHO.....the canopy is designed for good flow, and I have installed fans and have NO heat issues even with my glass tops. I only have between 6 and 8in of space in my canopy. Proper air flow can pretty much overcome most heat issues.
integlikewhoa
New member
Yup if he dont want to change the canopy MH probley for sure outta the question. Expessially if he wants the glass covers.
For prices of lights check out http://www.oceanencounter.com/ .
I bought my MH from there the HQI EVC set.
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