On Septic Tank Filter Design & Accessibility
Thus, it is best to install risers.
A larger sized filter allows you to lengthen the time
between filter cleanings.
And a finer filter (smaller holes) keeps more poopy
particulate remnants out of your drainfield.
All of these design features are money in the bank!
The more oils and fats and small poopy particles you keep out of your drainfield the longer your drainfield lasts.
A new drainfield will cost you at least $1500.