Hey still new around here myself as well but based on what I've been reading its a good idea to add a couple of gallons (I do not think there is actually a exact "right" amount) of water back into the black tank. The intention is to keep anything that does not get dumped down the drain from hardening. Some folks also say that this is good for the health of your dump valves.
Many folks do this even with a tank sprayer. My intention is to put some water back in after dumping. Maybe just enought to cover the bottom of the tank if I can figure out how much will do that - or a couple of gallons, few toilet bowls of water. I don't think it can hurt and is sounds like a good idea to avoid having dried, solid- "solids" in your tanks. Heh...
Side note: OP: I'm spending a great week "next door" over in Gatlinburg doing what I hope is my last round of "cabin camping" before our new TT arrives. I love TN and would live here in the Smokys if I could find a way to make a living!
TV: 2010 F250 XLT 4X4 SC SB 5.4L 3.73 - "The Blue Monster" (2013-2018) Traded at 100K
TV: 2017 F250 XLT 4X4 CC SB 6.7L PD 3.31 - "The Silver Streak"
TT: 2014 Starcraft Autumn Ridge 329BHU
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