6 or 8 bulb T5 over 120 gallon mix reef

ReefGeezer · Dec 19, 2022

I have an ATI 8X over my 90. I'd do the same for a 120 but add 2 Reef Brite LED Actinic strips. I change bulbs 4 at a time roughly every 12 months. I think 18 months would be safe and up to 24 if you wanted to push it in a mixed reef. You'll notice an increase in past algae and some drop off in "pop" as the bulbs age.

landlubber · Dec 19, 2022

nereefpat said:
To me, it makes more sense to use the 6 bulb fixture and add LED strips to the front and back.

Yikes!!
Assuming you mean every 6 months, that's still really overkill. I let mine go closer to 18 months.

in an 8-bulb fixture replacing 1 bulb every 6 weeks gives you just a hair over a year on each. replace a bulb, mark a date on the side of the fixture and wait 6 more weeks. I also used the dimming function so I also made a point of burning them in.
it would have been nice to replace 2 but depending on the bulb it meant having to raise the fixture or risk burning the top lying acropora. overall I just got tired of all the fuss and went led with a reefbrite strip

homer1475 · Dec 20, 2022

Never understood why people change bulbs like that?

I change all 8 bulbs in one shot, every 12 months. I've never had an issue with my LPS or SPS.

landlubber · Dec 20, 2022

homer1475 said:
Never understood why people change bulbs like that?

I change all 8 bulbs in one shot, every 12 months. I've never had an issue with my LPS or SPS.

well seeing as i'm right here i can just tell you lol.
imo changing 8 bulbs at once is about as jarring to stability as anything i can think of and while my 6 week rotation was tiresome it did work well.
if it works for you then by all means but 8 at once in my system would have been menacing. i'd either have to raise the fixture 18" and deal with light spill for months before i could lower it or screw with photoperiod neither of which is a good plan.
In a system comprised of acropora and zoanthids it was just a better fit to keep things down the middle or risk losing them.
again, you do you but that would have never worked for me.