Some chemicals have been found to cause problems in septic tanks due to their affect on the bacteria which helps breaks down solids. Check with the National Onsite Waste Water Assoc. (NOWRA) for details. I would recommend a septic tank filter in the outlet tee of the tank. The filter keeps large solids (above 1/16″) in the tank for further treatment and prevents the laterals from getting plugged. You will have to have the filter cleaned every one to three years (spray it off with a water hose) but this is minimal compared to damaging the system. For filter information go to http://WWW.ZOELLER.COM or contact technical services at 1-800-928-7867. Tony Renfro
[Edited by tonyr on 12 January 2001]