This closure has been a long time coming. The best answers to a clogged up septic field are nearly imposiible to find. There is propaganda everywhere to sell us one product after another. Septic plumbers want to sell an EXPENSIVE new drain field.
My best advice today is to start by adding risers to the tank & all of the D-Boxes, pump out the septic tanks & then hydro blast all of the laterals. Don't waste time & money on chemicals. As you watch the videos I have provided in the report below, you will see why chemicals are FUTILE to correct a failing septic field. Videos show us how effective hydro blasting the latrals are, and they become totally clogged up over the years.
Anything less is going to be temporary and result in never ending aggravations,