Join Date: Jul 2012
Location: Northern BC, Canada
I dont think so. Ive dont things like this a few times and never had problems.
The worst case was when I had a 29 gallon very heavily stocked community tank (maybe 25 large 2-3inch gold barbs, 20 whitecloud mountain minnows, im pretty sure some platies and corydoras too) for years as a teenager. When I took out the plastic decorations after 2 years of never being cleaned underneath (so I could try live plants) a ridiculous amount of brown organic material floated up and made it so you couldnt even see through the water.
I did a water change and spent 5 mintues using a net to scoop most of it out, and had no issues whatsoever.
Shrimp are more sensitive, but I dont think youll release anything that cant be solved by a water change and cleaning of your filter an hour later after its pulled all the gunk from the water.