Changing T5 schedule?

[csb123]

Hey fellow reefers,

It’s that time of year for me to replace my T5 bulbs (they are 1 year old.)

I’m curious if I can change them all at once, or should I change them over a few weeks. The BRS experiment shows that, over a year, they lose about 10% of output. I don’t want to shock my corals with too much light. I have a mixed reef with SPS and LPS.

Thanks for the input?

 

[Euphyllia97]

Best thing is to change them one at a time over a couple of weeks. I have changed my T5’s all at once without any negative response from the corals. I’m pretty convinced this is not the way to do it properly so I would not risk (especially when you have sps/lps) doing it this way.

Changing one by one over a period of time it is!

 

[cmaxwell39]

I have always changed mine all at once and then cut my light photoperiod back and slowly brought it back up over a couple of weeks. Never had any problems doing it this way.

 

[homer1475]

I've always changed mine at the 1 year mark, and have always changed them all at once. I've never had an issue with LPS, SPS, or softies.

 

[Bpb]

When I ran 8 Bulbs I’d change two a week at the 12-18 month mark. I’d start with the two outside bulbs the first week, and just work my way in.

On a theoretical level, they start off about 10% low in par from what their burned in intensity will be, so dropping the photoperiod at first is probably not totally necessary, as they’ll gradually
Brighten over 100 hours use or so. I recently changed out 2x250 watt halides that were 12 months old and didn’t modify my height or photoperiod. Just swapped them and everything just kept trucking along. No bleaching or retraction.