Lost smell and brown spotting

So, considering I know nothing about those products, nutrients you're using, in more "general" terms (you can try relate/translate it to what nutrients you have) I would use some calmag, sulphur, PK, sugar source (like molasses, coz it has general elements too) and microlements considering the smell went away since you dropped nutrients. Not shitting you. But then, your plant is kinda old already, dunno if it'll help.

Flushing is stupid, imo. It's for when you have excessive nutrients and your plant isn't healthy. Like if a plant grows in actual soil... right...do the math.