On a brighter note, I'm happy to see my chilli pepper monti regaining its colour.
I guess it's a combination of decent lights (6x24W T5) and better water conditions. This is mainly because of the frequent water changes while tying to export the velvet pathogens, AND that I have not needed to feed at all, as there are no fishes! Haha.
Only lightly dosed some planktons and coral food every few days. As a result, latest NO3 readings are zero.