switching lighting systems

[acepumping]

i agree, start with the light way higher to the same intensity as your old light, then slowly bring it down every week

[Rogue951]

I went from PC to Halides and shortened the photo period and slowly lengthened it.
Not sure how much of an actual jump going from PC to T5 is.

[mike31154]

The OP has gone from 95 watts to just over 100 watts of essentially the same technology in lighting, fluorescent. Not that big of a change in the end, although because T5HO are linear, you will get more light compared to a CFL that loses light due to the tubes being wrapped around each other. CFLs will bounce much of their light off itself due to the curving. The other factor that will make a noticeable difference is the quality of reflector between the two fixtures. If the odyssea has individual reflectors, the light output will certainly be more.

Good suggestions already here in trying to elevate the light for a few weeks & slowly lower it and/or shortening the photoperiod. You can also play with the bulb selection, different K values & colour like Actinic. Are all 4 T5s on the same switch or are they paired so you have the option of turning two on & leaving the other two off? If you have that option, you can start by running two for a few hours in morning/evening, with all 4 running only during the midday high light period. The key is to keep a close eye on how your coral reacts & make adjustments accordingly.

& oh yeah, when the T5HOs wear out, go LED. Shouldn't be too costly for a nano.