Yeah, the 18 hr rule is for CFLs or T5HO, and it doesn't seem that you are able to reach any intensity level with those sources that can cause severe photosaturation unless you really cram the lamps together and use really DIY reflectors, whereas with LED you apparently can.
I rarely run an LED scrubber at more than 12 hours/day and I recommend 9 hrs/day maximum for a start, and leave it there as long as it's doing the job. No need to increase it if it's not needed.
I rarely run an LED scrubber at more than 12 hours/day and I recommend 9 hrs/day maximum for a start, and leave it there as long as it's doing the job. No need to increase it if it's not needed.