Feeding update: I've begun increased feeding, because my Clown Tang
is getting skinny, and also because I want to try to keep a variety of non-photo NPS corals. So in my 90g with scrubber-only filtration, I'm currently feeding 4 cubes mysis, 5 ml Reed's Shelfish Diet (phyto), 5 ml Reed's Rotifeast, and 5 ml Reed's Arctipods (copepods), and 2 krill (for white eel) daily. Also one whole silverside weekly (for blue eel). For reference, 1 ml is about 2 pumps from a typical phyto pump bottle.
Since I increased to this amount, I'm now getting my first detectable readings in several months (Salifert). Nitrate is a slight pink... varies between .1 and 1. Phosphate is a barely visible blue; sometimes I'm not sure if it's really blue or not, but it's definitely not the crystal clear it used to be.
Pink coralline is continuing to take over, and the last two square inches of nuisance film algae disappeared last week. Some spots of cyano are still trying to hold on, but the coralline is overtaking them.
So the goal now is to see how much I can actually feed while still keeping N an P low. I don't think they need to be undetectable; I think my goal is to keep nuisance algae from forming, while at the same time being able to sustain non-photo NPS corals. BTW I added a few SPS frags on my new frag tray, and they seem to be doing well.