Chaeto lighting schedule question

[paparoof]

I'm wanting to maximize my chaeto growth to outcompete some trouble GHA spots in my display. NO3 is 5, PO4 is currently .2 but I'd like to get it (and keep it) below .1

I understand that photosynthetic organisms benefit from a dark/rest period, but I'm wondering if there are studies on how long that rest period needs to be - or conversely, what's the maximum useful light period before the chaeto needs a rest?

If I wanted to go for 16 hours of light per day, which of the following options would grow more cheato?
option 1: 16 hours on, 8 hours off
option 2: 8 hours on, 4 hours off, 8 hours on, 4 hours off

Can I push it to 20 if I do 10 hours on, 2 hours off, 10 hours on, 2 hours off? Does that still provide enough "rest"?

 

[MarshallB]

Don't quote me, but i've read it only really needs a few hours of darkness. Others have said they have had no issues running it 24/7 either. Honestly I think it comes down to what kind of light you are blasting it with. If you want to go 16 hours a day, then do 16 on 8 off which is currently what I do.