When should I pump my septic tank??

This is a very difficult question to answer! 1st, there are a number of questions to ask. 1. What is the size of your tank? 2. How many people use the system? 3. Do you use a garbage disposal? 4. What kind of soil do you have - good drainage or poor?? 5. How old is the system? 6. How much are you willing to risk damaging your drainage system? - Do you have plenty of property for new drain lines? - Do you have sewer available to hook-up to? - Do you have money to do the above? Well, the easy answer is the old recommended 3-5 years, but this is based on averages. Let's say: 1,000 gallon tank, 3-4 people, no garbage disposal, and average drainage system of less than 20 years of age. If you have a small (500-750 gallon) system - subtract a year For more people using the system (5+) - subtract a year. For garbage disposal use - NO MORE THAN 2 YEARS TOTAL (of course this depends HIGHLY on the amount of use. I've seen 2 people pack out a 1,000 gallon tank in 1.5 years!!!) For an older sytem, or a system with poor drainage - never go beyond 3 years (execpt for larger tanks with 1-2 people) Realy, there just isn't a good answer. The best thing is for you to know your system and your usage habits. For a new system or new home owner, pump early and base you next pumping interval on the solids accumulated. Although it's work, one can measure the scum solids levle easily. (it takes more to measure the sludge level) Keep in mind that no drainage system will last forever. Some last a short time with no apparent abuse, while others, with awesome drainage, last many years under abusive conditions. But, all things being equal, systems that are pumped regulary will last far longer than systems that are not pumped.