Keeping things in suspension makes for a happier black tank. I've found -- as have others -- that adding liquid is a good idea, esp. since I solo. I've used some of the tablets as well, but not on a regular basis.
"SilverLeaf II" 2015 30' Classic
2014 RAM 2500 Laramie 4x4 CC w/6.7L Cummins
WBCCI # 3430-Unit 21