Can i under drive my 250 watt hqi phoenix 14k bulbs??

I have a giesmann infinity 72” light fixture on my 220 reef tank and i’m having a hell of a time trying to find out a light schedule to keep from bleaching everything. The combination of running 3 250 watt hqi phoenix 14 halides just 5 hrs a day is bleaching my zoas at the bottom of a 26” tank along with my favias and lps. This fixture also has 4 80 watt t5 ati blue+ bulbs in as well that are on just 4-5 hrs a day before the halides come on and after they go off. I also added a reefbrite xho 72” xho actinic led fixture for color pop although i do not think this is the source of the bleaching corals..
Well now to my question..
I have 3 400 dimmable luxcore ballasts with a selector and was wondering if i took it off of the 250hqi setting and moved it down to the 250w setting would it be bad for my hqi bulbs or the sockets they plug into? Im just trying to get a little less par is all as i shouldve probably went with the 60” light fixture for this tank as this light is serious overkill, lol
Any ideas...