A typical tank may be 1,000 gallons, maybe 1,500.
Sludge reduces the operating capacity, so that suspended
solids are discharged quicker, exposing the drainage field to
larger solids.
It all depends on how the system is managed, and if you treat
it as a living system, you are not likely to need to have it pumped
often, or at all.
First thing I did after our first and only pumping was to use the 4"
opening in the top of the tank. I opened the cap, and used that
when I wanted to check on the sludge status. I was working
for the county health dept at the time, I used a tube made for the
purpose (trade name "Sludge Judge"). It's a handy tool, but way
overpriced. But if it keeps you from deciding to have your tank
pumped ONCE, it's more than paid for itself. Or it could be the
basis for having it done.
Sorry, but there are a few professionals in the tank pumping
business, and a lot of amateurs. When it's pumped, the SLUDGE
needs to be removed. Best way I knew to see that happen was
to remove the tank cover. I probed the tank to know where to dig.
Lot easier for them to just poke their pipe down and start pumping
whatever worked its way to the pipe, but you should be able to
understand the difference.
A typical recommendation is for a pumping every 3-5 years.
I did what was necessary, including keeping track of sludge level,
and never had it pumped after moving in.
By the way, when schools on an aerated tank are going to be
closed all summer, they will frequently flush down dog food for
the little bugglings to eat. Same applies to a homeowner going on
vacation.
On Feb 16, 6:02 pm, "Dan" wrote:
My wife & I are considering buying a house with a septic tank. I have never
lived in a property that had such a system, but have always heard they can
be troublesome (most things can, I guess). System is described by MLS as
"Two bedroom septic", which I gather indicates its capacity. If anyone can
give me some feedback on just how problematic septic systems can be, any
questions I might ask the realtor when we see the house for the 1st time (he
probably won't KNOW, but at least I'LL look like I DO ;-), any other general
comments on septics, etc. There would be just the 2 of us living in the
house, which is located in the Seattle area.

TIA

Dan