Any thought to ditch the chaeto and go with some GFO in a reactor for phosphates? You can increase water change percentage to lower nitrates as well.10% wc per week.
Big skimmer
12 liters Seachem matrix in 3 baskets. Maybe i need better flow.
Smallish dsb
Cheato- which won't grow..
I think most of it is just that the corals aren't pulling as much as before. When they were growing like mad..