OK, I'm a "Septic Tank Virgin". Never had one before but just bought a house that has one. Searching around for some kind of information I came across a couple of 2nd hand American books on the subject. Obviously one needs to take much of the legal stuff with a pinch of salt but the two give a similar view of how the whole system works (pretty obvious now I've read about it).
Both suggest that it might be a good idea to try and get an occasional view of the "cross section" of what is in your tank. They both suggest obtaining a piece of see-though rigid piping, pushing this down into the tank, putting a stopper in the top and the withdrawing it (a bit like what I remember as a "pipette" all those years ago at school).
So, my question is two fold:
1) Is it worthwhile? 2) If it is, where does one purchase the necessary piping? I can find narrow bore flexible see through piping and, of course, down pipe for guttering in grey or black but not what I seem to need.