robgraham wrote:
Just out of interest - what criteria does one use to judge when a
spetic tank does require pumping out? The interpretation of the above
thread is that a cess pool requires regular pumping - yearly? - but
that a septic tank rarely requires this treatment. I suppose it does
depend on the size of the septic tank and the domestic throughput, but
that still brings back the question -- when?

I had mine done after fully 15 years recently and the operator wasn't
too impressed ! What seemed to be upsetting him was that the crust was
hard and therefore required more work to process.

Rob


Well they all want you do do it yearly...but as you have discovered, you
can leave it a long time.

Id say when the crust turns to something a cat can stand on, its tome to
remove (the crust) and when the sediment compromises the interchamber
exchanger then its also time to get THAT out.

My klargester seems to like about 3 yearly attention..its specced for a
6 bedroom house but there are only two of us. A big septic tank - every
5 years or so probably.