I have one like this:
https://www.amazon.ca/Flojet-1855500...macerator+pump
I carry a 45 gal.(Cdn) plastic barrel for grey and black water in my TV. I also carry a 25 gal. plastic fresh water barrel with a 12v whizzer pump to water the trailer. They add very little actual weight, but provide great peace of mind. I have a cap on my truck, so it doesn't stick out at all.
I have only had to use the setup once or twice, but it beats the heck out of packing up, driving 25 miles, or more, dumping, then going back to your spot.
I use a well marked ordinary "Walmart special" garden hose for output from the macerator and another well marked WM hose for feeding and flushing the macerator. When I did pump the tanks, I made sure there was lots of water in the black tank.
Sounds like quite a performance, but, as I said above, sure beats moving the trailer just to dump.
I ran a 12v feed back from the batteries to just above/near the dump valves. The macerator has a on/off switch on a length of cable, so you can stand off a bit. Works like a charm.
