TDS spike/Shrimp Die off nothings changed?

Hey everyone!

So I have a random question. My 20L Crystal Red tank was going great until the last maint and trim for some reason.

I changed just as much water as I normally do, and everything usually hovers between 120-140 TDS.

Last change was a slightly higher than normal 20%, instead of my normal 2-3x a week 10% RODI remin water back to 120 TDS, the only thing I really did was trim a lot of the riccia down and retie it down to the rocks...

Since then my TDS has nearly doubled, the riccia on the rocks is not a happy green like it's been and the hornwort (which I've never managed to kill) is browning in some spots.

I'm still dosing the same amount of ferts, nothing else has changed. My Dwarf Sag is still sending out runners like crazy, my crypts look beautiful, so what happened?

Any help would be greatly appreciated, I've gone from about 24 Crystals down to about 4 that I can see, there's been no jumpers and I checked in the filter today and there's none in there. When I did another water change today I didn't see any bodies or anything, it's like they're just disappearing....they can't jump out because I have a hood on the tank.

I'm really freaked out here because these are my favorite shrimp, but there's something really awry in the tank...

All of the params look good from PH to nitrates and ammonia....everythings right where it should be.

Thanks in advance!