Question: MH Lighting height from tank surface

[Deep_blue15]

Question: I switched lighting when moving to a larger/new tank (135g to 225g). I was running T-5 lighting, but switched over to 3x250mh w/14k Phoenix bulbs and 8 x 39w T-5 actinics. All bulbs are brand new.

The "Current" brand lighting MH fixture stock legs are around 4" lift from the tank surface. My tank is 72" long x 30 " deep x 24 " tall.

My corals are not doing as well after 4 months. Lots of tip burn, lost some, etc, even though I placed these corals lower in the new tank than when they were under T-5's.

Tank parameter's are good. I've had Salt tanks for 6 years and have not used MH. I thought the T-5 lights were more intense than MH with PAR readings.

I can keep moving corals lower in my tank, but considered moving my lights up by hanging them. Does anyone have a similar set-up and can provide how high from the glass top they have their MH's? I have an SPS dominated tank with LPS and a few softies.

Tank Parameter's:
SG: .24
PH: 8.26-8.6
Calcium: 450
KH: 10
Mag: 1400

Timing of the lights:
All 250w MH 8 hours per day and the T-5's 9 hours (half hour before and after the MH schedule) Should I reduce some of the timing on the MH's?

Any recommendations are appreciated. Thanks in advance.

[dzfish17]

When I had my 210g reef I ran 3-250w about 8"/9" above the water. I had mostly lps and a few sps. Thats alot of light and starting them lower and then moving them up is probably better. My MH were on 6 1/2 hrs per day. GL

[125G Reefer]

Its an acclimatioin process. Hang Halides high forst off, then slowly lower them over time. A few weeks.