I'm looking for some sort of device but I'm not sure what it is
Here is a picture of a recently activated gunge tank! When I've set up game nights with this homemade setup for friends before, I've scraped up the gunge in the pool below with a heavy duty dustpan and put it in a bucket for reuse. It works but it takes ages and it's hard to get it all.
Can any gungemasters recommend some sort of pump or wet vacuum to vacuum up the spilled slime? If it could also pump gunge up into the reservoir again that would be amazing - it would make it a lot easier to fill the tank from a bucket on the ground without having to climb up precariously. I've looked at some potential candidates (trash pump, diaphragm pump??) but I'm not sure what would be best for handling thick liquids like this.
Peristaltic pumps are good for viscous liquids. They also have the advantage that the payload doesn't ever actually touch the pump head, so you don't have to take it apart and clean the rotor, just flush the tube.