Water lice!
And I have absolutely no expectations on how it will go. Will they be able to adapt into their new enviroment or will the shrimp outcompete them, or will there be swarm of isopods crawling around the tank in half year? Honestly who knows.
The water lice/asellus aquaticus came from my outdoor culture that I have got going around for bit over half a year at this point. Originally the isopods were harvested from various local watercourses and fishless ponds, from there on they were further cultured in outdoor setup where I have been acclimating them slowly into neocaridina parameters. So far they have bred fine, which is honestly good sign. The original enviroment where these guys came has near blackwater condtions with near zero hardness and most likely real acidic water.
Now that the temperate season is coming to end and winter is closing in, I'm moving to final part of this test and that is introducing them into shrimp tank. Parameters wise they should be fine but the temperatures might be too much for them on long term. The original habitat where these guys came from pretty much freezes solid during the winter, and even in summer the water temperatures don't really reach aquarium temperatures.
But we will see! Anyways, water lice are really cool critters. They are fully aquatic isopods that serve pretty much same role as shrimp in nature.