There is conflicting evidence about the use of water softeners and septic tanks. Generally, the industry opinion is that the backwash from water softeners harms septic tanks.
Whilst the Muck Munchers are effective in saline solutions, the real problem can occur in your drainfield.
Our advice is that if you have a septic tank and are planning on buying a water softener, play safe and look at an alternative ‘saltless’ system. Simply search ‘saltless water softeners’ online. I do not personally have experience of particular brands so am unable to make any recommendations to you.
Salt Can Destroy a Septic Tank System’s Soakaway
Excessive sodium discharges can affect the ability of a soakaway to digest sewage effluent. Salt in small quantities has minimal impact on the septic tank environment, but over time big changes can occur in the soakaway through ‘sodium binding’.
What happens is this – when sodium causes chemical exchanges, clay particles bond together and form a waterproof layer, so the soakaway fills with water, blocking the soil air upon which aerobic bacteria depend. Anaerobic bacteria take over and by doing so increase the problem further, by forming a biomatt of black slime, which can quickly block the entire soakaway.