250w 20k HQI enough for sps?

[flyhigh123]

250w 20k HQI enough for sps?

I have a tank 30 inch high.6 feet long. Are 2 250w 20k HQI DE enough to have SPS?

I was thinking the 20k is less par, but i do like the color. I do have 2 80w T5, but prefer to only use them for dusk and dawn to save on electricity.

Thanks!

 

[rmalone]

Well you can run the mh on either end and have enough light on the ends of the tank with a dark area in the middle. Or you could push both lights more to the center and have dark areas on both ends. One or the other, I am doing the exact same thing, you will not light the whole tank on 2x250 for sps from one side to other, simple as that.

I run my 2x80w t5 from the start of lighting until the end of the lit period. The mh run 1.5 hr less at the start and end of the day. You will find that without the t5 there will either be dark areas in the middle or on both ends of the tank, depending on how you position the mh. With the t5 added to the mh the human eye doesn't pick up the intensity difference, but the corals sure do. Either run the t5 all day w/2x250w mh or run 3x250mh and the t5 at the start and finish of the day. 2x250w mh on a 6 foot just doesn't look very good all by itself, nor will they support sps across the entire length of the tank all by themselves. 2x250w mh and 2x80w t5 looks very nice but in no way do they support sps growth across 6ft of tank, you WILL have holes. Works out great if you have a few lps that you like to place in the lower light holes between or at the ends of the mh's.

 

[dzhuo]

you will not light the whole tank on 2x250 for sps from one side to other, simple as that.

Obviously, using more bulbs and lights would help. But it's certainly possible to light a 6' tank with 2 MH bulbs with the right reflector. The LumenArc and LumenMax reflector, for example, both have good 3'x3' coverage when Sanjay test them:

Product Review: Analyzing Reflectors: Lumenbrite III, Lumenmax Elite, Lumenmax, and Lumenarc III

The lumenarc III and the Lumenmax reflectors provide a large area of light coverage and hence are more suitable for tanks wider than 3 ft. At similar distances they both provide a large coverage of area where the PPFD values reach between 100-200 micromoles/m2/sec. In my experience, if a user can achieve PPFD values of 75-100 at the bottom of the tank, then they will have enough gradation of light in the tank to find places to keep most photosynthetic corals happy in the tank. The Lumenmax reflector at 30" provided a larger area where the PPFD values were greater than 200, as compared to the Lumenarc reflector. Hence, the reflector will be able to provide a higher intensity deeper in the tank, thus making it a better choice for someone looking to light a wide tank that is deeper than 30", or for providing the ability to grow higher light corals lower in the tank.

I am also not sure if you want high intensity coverage throughout the tank since you won't be able to have area where you want lower light corals.

 

[danil]

Very true with all replies. I just want to add a note about ballast. I was running my 2X250 MH with some unknown generic brand of ballast and tank was pretty dim. I switched to Icecap and probably double my par . So with good ballast and right reflector with big coverage like LumenArc plus some T5 to smooth things out its possible.

 

[flyhigh123]

I'm running the sunlight supply hqi reflectors which look similar to the lumenmax. Also my ballast the the blue line model.