New Metal Halides

[Casey]

Hi I need your help again,I have installed one 175watt 12,000k
metal halide on my tank and am getting ready to Install 2 more 250 watt metal halides,my question is , is 675 watts enough on a 100 gal tank?? and I have noticed the 12,000k bulb puts out a blueish light I want more of a natural yellow light whayt is the difference in 5,000k 4000k I dont understand this kelvin stuff
how can I get pretier light? thanks Casey

[Minnreefer]

Many people use the Iwaski 65k bulbs, us included on a tank with good luck,It may be too yellow for your taste without actinic support but you can always add that later. I would look at the dual PFO ballast and the Iwaski bulbs from www.premiumaquatics.com HTH

Jon

[Rick O]

In a nutshell the lower the kelvin the yellower the light will be. 10,000K will appear to be white with no yellow or blue tint to it. Lower kelvin bulbs may affect the coloration of some SPS turning them brown. I have the 250 watt 6500K Iwasakis. I don't particularly care for the color of that bulb by itself so I supplement with actinics. This is just my observations. Everyone has their opinion on what looks best so go with what you like.

JMO, FWIW

[SteveNichols]

one thing to note is that the highest PAR (photosynthetically active radiation) is higher on the 6500K Iwasakis than on the other K temperatures. That, in general, gives higher growth rates. many people find better coloration using higher K temps. Here is a link to an analysis of several 250W mh lamps. HTH

[Jimbo]

Hi here's another link that shows pictures of different lighting combinations.

http://www.coralreefecosystems.com/ltg_bulb_color.htm

Hope this helps