Tampa Bay Plumbers performs septic pumping in Tampa everyday. In this particular project, we discovered the tank has not been pumped since 1998. When this happens the solids accumulate in the bottom of the tank and the top of the tank. Eventually the system stops working. The purpose of a septic tank is to trap solids and to allow for good bacteria to break down those solids and turn them into sludge. The septic tank should be pumped every 2-5 years depending on usage and a chemical treatment should be installed to kick start the good bacteria life in the tank. Not having your tank pumped regularly is the equivalent of not changing your motor oil.