In my opinion you should always add a few gallons of water after dumping. If you are traveling the sloshing helps clean the tank. If stationary the water helps the chemical work better and helps prevent the sh*t pyramid.
TV: 2013 F350, Lariat, 4x4, CC, LB, 6.7L Powerstroke
FW: 2013 Jayco Eagle Premier 361 REQS
Additions: Onan 5500W LP Generator, Surge Guard TS,
.......Roof Satellite Dish, Vent Covers, Bedroom Vent Fan,
.......Rear Reciever, 12V DC Outlets (6), 320W Solar & Controller,
.......4 Lifeline AGM Batteries (600 Ah @ 12V),
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