We also have the Sani-Con macerator pump. I've only had to clean it once when, apparently, a friend of mine's son dropped a piece of gum in the toilet and I didn't know it. It jammed the impeller when I emptied the tanks.
I like using both systems depending on how we are set up at the campsite. Sometimes, the slinky will not quite reach the sewer outlet but the Sani-can will (with it's normal length hose). Our toilet is also a Macerator toilet which helps ease the work on the macerator impeller.
JimM68, I don't quite understand that your bypass doesn't work well. If I have the macerator connected to the our wet bay sewer outlet and I leave the gray tank valve open, it will never back up. Our gray tank holds 70 gallons.
In a normal setting, we will empty two gray tanks to one black tank with two people using the motorhome (black tank is 40 gallons). And generally, I wait until the tanks are near full before emptying. If we have several loads of washing to do, I might empty the gray tank more often in comparison to the black tank. When I use the macerator connection, I will empty the black first then let the gray water back up into the black tank to 'kind of' backwash it.
We also have the Sani-Flush system too to clean both tanks.
MM.
