T5 HO Bulbs

[onecansay]

I am not looking to open a debate about which type of lighting is better, but which type of bulb combination would work best for coloration.
Currently am running 4 36"x39 Watt 18 K bulbs with 2 36"x39 Watt Actinic. I was thinking of replacing 2 of the 18 K for either 6700's or 10K.
Would the 6700's create a potential algae problem?
Any and all opinions greatly appreciated.
some call me frank

[Jason McKenzie]

6700K should not increase the chance of algae. Anything above 5500 should be OK. It's really personal preference. I like a 'less yellow' look so I would go for the 10K

J