Full timing black tank dump n flush

[Larry drv 7*3]

2009 DRV Elite Suite 36TK3, living full time stationary.
Have been dumping black tank on Sat. And Tues. Clean with tank flush system but still not totally cleaned out. Will flush 10 full bowls then open dump to wash out tank but still getting clumps.
How many days with 2 people do you dump?
Sometimes tank is totally full.
Should i dump every other day?
Have porcelan toilet with wall switch for fill and electric ball flush. My previous 5er i stepped on pedal and left hose wand down into tank filling it to flush out complete tank interior.