I asked the county inspector about adding a dump and he said I couldn't get a permit to add it to my existing system. I told him how it would be used and he said it would be fine and to do it anyway. I doted over the septic in my previous house. The family that was in this house were MAJOR water users and they never added enzymes etc to the system. The guy used to turn on the shower and then go make coffee and drink it before he took his shower and this system checked out great in the septic inspection - as good as my other system looked. I used to spend a lot of money on septic additives and fret over every little thing but not anymore. Don't use chlorine or other harmful chemicals and watch the water usage.