Probably a "No brainer" but...

[btldreef]

He light I ran was supposed to have two. In the back, two in the front, I just took out one bulb on each sudebecause it was too much.
If you're going to do a separate unit for the T5s, I would not go with anything crazy since you're really just using them for some extra color and for dawn and dusk. With my 250s, I ran GLO ballasts for my T5 actinics, they work fine for those types of applications, and they're usually cheap.

 

[caz2022]

Heres another question, does it have to be T5s for the antics? What about PC, VHO, or the Blue LEDS?

 

[al&burke]

Just6 for the record aren't T5 bulbs alot cheaper than replacement PC bulbs. I think this should be factored into the equation. JMHO

 

[btldreef]

T5's are usually cheaper than PC's. I learned that the hard way. My 96 watt PC's were about $65 a piece.
I never used VHOs, only because no one around here keeps them in stock. For actinics, since you're using halides, I'd go with the cheapest option.

 

[cryptics]

I run 2 x 250w MH and 2 x 54w T5's on my 90g. I needed a chiller. My rockwork goes about 3/4 of the way up and I have to be careful about what i put up top

 

[reefkprz]

I have found using 2 250whalides with 2 110W vho's that, while I cant't just throw anything up on top at first I can acclimate almost anything to the high light found centered under the halides at the top. Just have to slowly move things up and center them more every couple weeks to allow them time to acclimate to the light. even "low" light corals like mushrooms. acclimation is most people problem when it comes to that, they want to place it right away, you cant always do that when you have buku light. in most corals they can easily be acclimated to higher light but can also tolerate low light, its the speed in which you make the change that determines the corals survival.