My lighting is a catalina 36" 4-39watt t5ho fixture. I have 2 lights on for 10 hours and all 4 on for 4 hours. No dimmer. I just got a par meter from Hoppy and was shocked at how low the par values were. Right under thelights im at 200. The top of the plants was 100. Middle was down to 50. Bottom was between 1 and 30. While these sound normal the part that surprised me was the back of the tank is like 10 at the top and like 0 at the bottom. I looked at the fixture and see that sure enough the reflector sends no light to the back.
So I purchased LEDs. Should get here wednesday. I should have an even distribution of light across the whole width of the tank.