going back to mH

[George]

You have to know your MH bulbs in order to create a good combination of MH/T5. Ushio 250W 10KK peak at 420 nm. If you used actinic T5's that also peak at 420 nm, you didn't get any benefit from the T5's in terms of color. Try to get T5 bulbs that peak at 450 nm/460 nm.
Sajay's lighting DB is a good site to look up your MH bulb spectrum.

Originally Posted by Tyler Werbowski

In the used 250 W MH set-up I got a set of 10000K Ushio bulbs and 10000K Aqua-line bulbs. I hoped two 54W actinics would off-set the yellow. Not even close and I bought 14000K Phoenix's the next day. IME the actinics are totally overpowered by the MH's and do not accent the corals at all when the MH are on. My actinics only come on when the MH's go out for a dusk to dawn effect.