what's the deal with day/night bulbs (t5)

So I am currently deliberating between MH and T5, and I had one question about T5.

I was going to get 2 108w GLO fixtures, one with daylight bulbs, and the other with actinic bulbs.

Do you only run two bulbs at the same time? Or do you run the day/night bulbs together? It seems that if you only ran 2 bulbs at a time, the 108w wouldnt be enough for corals in my 55G tank.

 

You run the actinic for 10 to 12 hours and the daylights for 8 to 10 hours. All four will be on when you turn on the daylights. Just turn on the actinics an hour earlier then the daylights and turn them off an hour later than when you turn the daylights off.

 

You run them all at once. The actinic bulb is not for night time use. They create a light that is used to accentuate the colors in corals. This light just looks dark to us. The light created is 420-450 nanometers, aka barely visible.

 

check your PM.. you could always replace 1 actinic bulb with a ATI blueplus+ which still has good growth/par and blue tint look down the road. so really you'll have 3 bulbs out of 4 that will help with growth.

 

I actually really don't like the blue look, so would i be better off with 4 daylight bulbs for maximum growth?

 

sure.. go with (4) 10k-12k range bulbs.

ATI,giessman,UVL

 

For the best growth, you would want 4 x 7500Kelvin Bulbs. This is way to yellow for most.
10K bulbs are a stark white, 12K have a hint of blue, 14 more pronounced blue, 20K deep blue.

Of course, each manufacturers varies just a bit.

Most enjoy somewhere in between 10K-14K. 10K will get you good growth and look great.
I would still run at least one actinic for that "color pop".