Hi all, First post

[Doug]

Jedi, I think if you run a 12K on one side and a 65K on the other, you will get a contrasting difference in the two sides of the tank.

At least mine did. I ended up running a 400w 12K in the center, with a 175w 10K on each side. That gave me the nicest colour.

If I may offer my opinion, as you already have 4 actinics running, a pair of 175 watt 10K German bulbs, in combination with the actinics, would give the the colour, par, and best bang for the buck. The German 10K bulbs are some of the best on the market, in the 175 watt version. I would not hesitate using them for 18 months, myself.