I just set my qt tank up when I need it with a small hang on spounge filter and a piece of 3" pvc
for the fish to hide in if they feel the need. I just mix up some fresh saltwater everytime I need it. It works well. I just make sure the saltwater matches the salinity of my dt. Other people might leave it set up all the time but I have no need for that. As for pwc
on my dt I have a mark on the side of my tank and I got a small drill operated pump from menards and some rubber hose from ace hardware and I pump it out and then reverse the direction on my drill and pump it back in out of my 5 gal
bucket. It works great. To keep fish from getting sucked up in it I put one of those nylon traps that zip tie on the end of the hose that are supposed to be used for a clothes washer. I built the whole thing for $20 and it took 20 min to put together.