Switching from PC to t5`s

a 6 bulb should be awesome for your 75 just got to take into consideration how wide the unit will be. some units can be kinda wide. i would definately do individual refelctors though. 6 bulb would be awesome and you'll love the more intense light and better coloring. i would look into what Eric "llebcire" did for his 72g bowfront he used a catalina setup that was about 150 bucks i think, might want to look into those

 

I just upgraded from VHOs to T5s and there was a ton of difference. I have 4 T5s and one of the VHO's on my 72 gallon and it's great plenty. I think Ice Caps T5s are the best in their category because their 660 ballast is wired to overdrive the lights to 85watts for their 4' bulbs. You can get a lot more light for the space, just make sure you get a nice size fan because they get quite hot. I am using a fan from an old air hockey table and it works great, plus it was free, so it's even better!

 

I have a 4x54 t5 fixture and it is way plenty for my softies and lps. I also got a catalina fixture and it's working great.

 

I got a deal on the Catalina when it was $169 - now they're back @ $275.

http://www.catalinaaquarium.com/pro...d00493b203
54w x 4 is quite a bit more light than most people give it credit for.  In terms of PAR, 216w T5 is about equal to 400w MH, but you would need to line up several 400's to get the same output as the MH is more of a direct light, hence the shimmer lines, whereas the T5 is uniform across the tank.  There are threads on RC where people are geting better PAR @ the bottom of their tanks w/T5 than they were measuring w/MH's.
I'm getting great growth from corals that need intense lighting, i.e. montis, mili's, procillipora, birdsnest, slimer, etc. and have had to reduce the photoperiod as I was experiencing some bleaching.
Current photoperiod is actinic (460nm) from 3pm to 11pm and 10k's from 4 pm to 10pm.
-Eric

 

I also have questions on this subject. I currently just have a single dual T5 fixture on our 75. I know I need more wattage so I was thinking about the most cost effective way to add more and if I add more T5's or some VHO?? From what a lot of you are saying maybe just more T5's? And what is the best to go with as far as fixture?

 

i would just do all T5's wouldn't add any VHO's cause it wont help your cause all that much, VHO are mainly used for accent lighting i think with metal halides not as main lighting for a reef tank, for a FOWLR or just a FO VHO's on their own would be fine as would just a NO T12 light