Red Gracilaria - what is optimal K?

[vester_72]

Hi - just wondering what the optimal K is for Red Gracilaria?

I have it in my fuge under 110w 10K PC lights and it grows VERY slow.

I just swaped out 1 10K bulb to a 55w Actinic - will it like the blue light better since it is a red algae? Or should I switch back to the 10K?

Thanks,

Jason

 

[Mariner]

I'd be interested to know the answer too. Mine is turning a little green on the ends :eek1:
Mariner

 

[billsreef]

Gracilaria sp. are real nutrient hogs. Slow growth or loss of color is more likely to be due to lack of nutrients rather than the light spectrum. While real reds are typical of somewhat deeper water and therefore bluer light, I don't think the K rating of the bulbs is the problem. The higher K bulbs don't really put out more blue, but rather less of the other colors in order to look more blue. No matter what bulbs your using, you more likely to get better growth by increasing the nutrient inputs and using an iron suplement if you don't already.