Saltwater and the septic tank

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Senior Member Wannabe
Feb 3, 2007
Western Michigan
Creamhorses - Welcome! A great board, where I have learned a ton of stuff. I dumped a lot of Saltwater in my septic tank when I first started and I definitely think it affected things.

I now dump in the woods, but your right there really is no good place to dump IMO.
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AC Members
Mar 24, 2008
Very interesting....Imagine the bacteria cout in a single visit to "drop the duece". I would say large quanities such as 10 plus gallons every single week might effect things. Better to throw outside in different areas and let mother nature work it out.


Registered Member
Dec 30, 2013
septic and water changes

Fresh water is ok to dump the bacteria in it will be ok but saltwater is a different thing.
Just like in your tank once you add salt it stays there and will absolutely kill off your beneficial bacteria in the septic even if your only adding a little it eventually adds up and the salt doesnt leave it upsets the whole balance.
Many years ago it was recommended to add freshwater fish guts to your septic for the beneficial bacteria to your system i have done this and i dont have to buy any.
Just my FYI


Global Moderator
Staff member
Jan 11, 2013
West Falls NY
Real Name
Nice information!The most important system in our home is the septic tank. Therefore, it is very important to pump them regularly, as it gets blocked due to accumulated waste products and to increase the life of the septic tanks.
Super old thread here, but you are 100% correct clara, except "tank" should be 'system'.

This was the OP's problem. Provided the OP's system is somewhat functional, their only problem was they waited too long between septic pumpings. Pretty common for people to neglect this. Non-digestible items will build up over time, causing that nice layer of floating nastiness to grow so thick, it plugs the outflow to your sand filter or leach bed.

Dumping large amounts of salt water would be bad for a septic system, just like using large amounts of detergents, soaps, bleach, etc. If it ain't natural and digestible, it shouldn't go down your drain if you're on a septic.

Additives are absolutely not necessary. Many of them can loosen up your floating scum layer to the point it liquifies, flows into your leech field and plugs the whole deal. Newer systems have an effluent filter to catch this (Zabo filter), but regardless, that's still going to plug, have to be dug up to access and clean.

I'm no septic expert, but have replaced systems and lived with them for many years. Good times. For those on municipal sewer systems, you've got it made!