10000k vs 20000k

[spragro1]

What is the diff btwn a 10,000k and 20,000k MH bulb - i replaced my 20 with a 10 and notice the light has a more yellow color - the corals have puffed up more as a result = why is this and which bulb is better long term

[ksarauer]

A 10k bulb will have a yellow tint to it, and a 20k bulb will have a blue tint to it. Most of this is personal preference as to how they look. Not exactly sure why the corals look puffed up more.

Also a 10K light is more intense, and you should not have to run them as long as a 20K light.

[drives300]

Actually 20 K are actually very purpleish. To me the color is overwhelming but its great for making SPS colors pop.

10k can be bright white or a tad yellow depending on the bulb and ballast. I run 10 ks that are white

[liv]

as to why they puffed up.. if you replaced the bulb.. its probebly because it was due... ( old ) so putting in a new bulb would give more light to the coral.. hense why its probebly all puffed up.. ( its happier )

[tkang69]

The 10K lighting is much more intense, and generally has better PAR. The corals are probably responding to the stronger lighting. Keep an eye on them to make sure they don't bleach, as a result of the sudden increase in lighting.

[Ti]

10k grows more