[pogodzib]

Are all of your bulbs 12k bulbs, or do you have different par levels? You should be able to get a mixture of bulbs that will give you awesome color and growth.

I don't know how many bulbs are in your fixture, but as an example, here is what one, very highly recommend user, recommends for a 6 bulb fixture.

Front
Blue Plus
Super Actinic
UVL Aquasun or Ge 3000K
Aquablue
GE 6500K
Blue Plus