OK major question here for you... Do you leave the black tank drain valve open?
NEVER DO THIS... always let the tank fill with waste then empty it... there is never enough water in an RV flush to carry away the nasty stuff if you leave the drain open you will loose the liquids but the solids will stay behind and eventually clog the tank...
2004 Chev Silverado Duramax optioned past the max. 2009 Jayco Eagle 308 RLS 765 watts of solar, 6-6 volt batteries (696 amp hour), 2000 watt (4000 surge) whole house inverter.
140 days boondocking in 2016
211/2015, 196/14, 247/13, 193/12