Do you use Powder or Liquid Detergent?
I do it when it needs to be done...about once a week. I use liquid because back when we had a septic tank in New York powders didn't disipate as easily as liquids, besides liquids don't clump
I use liquid All Free & Clear, and then I use powder 2000 Mule Team Borax to boost the detergent.
liquid if I buy it
powder if I make my own