Hello Swissian,
Thanks for the input. I rescaped today. I actually fished everything out, cos I figured I would be stirring up a lot of crap... and I did. I also thought it was a good opportunity for me to do a rough headcount. Turns out I had 18 shrimpies instead of 15...

how odd, I only paid for 15. But that tells me that none of them died when I first introduced them to the tank :biggrin: Of course I can't say the same now after today's ordeal!
I removed all plants and deco items and put them aside, then I fished everyone out and put shrimps along with the fishes in a bucket of their own water. Then I went full attack with a small gravel vacuum, not that it helped me stir up any less crap later on when I made a mess of the rest of the water. After I was finished rescaping, I let the heater and filter run for an hour before re-acclimatising them for another hour. Poor stressed otos seem to have regained their composure, and shrimps had their full colour return within the hour, so I guess they're alright. Guppies seem fine no matter what.
All I hope for now is that the berried female births safely, and the other female feels safe enough to breed. I hope I didn't kill any shrimps from the stress. Next time I want to move something I will be a little less extreme I guess
By the way, I'm not Swiss, but I live in Bern. Originally from Malaysia. Valais is beautiful :icon_smil: