Installed this system back in 1999. As per manufacturer, needs to change peat moss filter every 7-8 years. 1400$ in 2006, 1900$ in 2014 and 3500$ in 2023. This does not include the annual 'scrape the top of the peat moss fee' of 160$ annually, and the regular septic tank pumping every 2-3 years at approx. 300$. Don't touch this system as they will charge you the price of the day, unbelievable. Also, had to reattach some parts a couple times as the technician that comes annually had not done his work properly. Will probably have it replaced for a conventinal septic.