MH noob question

Hi everyone! Just joined and somewhat new to the saltwater game, I have a noob question about MH or probably just lights in general. I have a 250w 15000k mh bulb and a 70w 14000k mh bulb...i understand that wattage has to do with how much energy/electricity is used but what is the 14000k/15000k? i tried to search to see if this topic was already created. thanks!

 

THe Kelvin deals with what spectrum of light is given off by the bulb.

M

 

Basically, a 10K bulb is supposed to be plain white (although normally looks an ugly yellow In my opinion, but thats just what i think). Anything higher than that (next would be 12K, 14K, and then your 15K, and the highest that most people use are 20K. I think their might be even higher but no one ever uses it) looks more blue.

15K is supposed to be a nice happy medium between good growth (lower ones get better growth rate) and best color (higher K ratings are more blue, thus, better coral color).

hope this helps

 

Just curious but if your lights are on a lot for coral growth how do you keep algae in check? I'm a noob as well lol.

 

buy running a low nutrient system. if there is very little food, and inhabitants out compete algae for it, algae won't grow.

specifically buy keeping low nitrate and phosphate(corals don't like these).

 

I wanna say its not technically the spectrum but simply the color the bulb puts out.
k stands for kelvin, the number comes from the temperature a black body radiator is at when it radiates that color.