I absolutely LOVE discus. Gave it up several years ago and got into salt the last 2 years. Wow!!! So far....huge money pit. It’s had its ups and lots of downs. Lots of lessons learnedI’ve felt the same way dude. Sorry to hear all that’s been going on. The corals in my tank aren’t looking happy either.
It feels like I’m going through a minefield at times when I try fixing things.
At the end of the day I feel stability is the key. Which means adding more equipment which means more cost.
I hope you like discus keeping if you go that route. Freshwater was on of the least stressful times I had with great returns.