Any concerns putting PBW into a septic system?

[Tom R]

I brew about 15 batches a year, cleaning up with PBW. Although I've been using PBW for a year or so, I never stopped to think about how it might affect my septic system.

We had the 800 gallon tank pumped recently, and I waited a few weeks for the tank to be at least partially filled before using PBW again, so at least it would be more diluted.

Don't want to kill the good bugs in the tank...

 

[Bilsch]

If you are really worried save your PBW in an old plastic barrel and then add your spent Starsan while periodically checking with your pH meter until between 6 and 9 and you should be golden.

 

[RPh_Guy]

Don't want to kill the good bugs in the tank...

The release of hydrogen peroxide (H2O2) from the sodium percarbonate in PBW (and other "oxygen" cleansers like OxiClean) is responsible for the anti-microbial action.

The H2O2 tends to release and break down quickly, within 1-2 hours at hot temperatures and within and 12-24 hours at room temperature. You can tell when it's dissipated because it will no longer be fizzy or cloudy.

Cheers

 

[Bilsch]

It's not the percarbonate that's the worry, the other ingredients sodium metasilicate and sodium percarbonate are very basic and you shouldn't put anything in your septic tank below pH 6 and above pH 9. So that's where your spent Starsan comes to the rescue.

 

[RPh_Guy]

So he could just add some cheap acid right away if he wants? Vinegar or citric acid, for example.

 

[Bilsch]

Absolutely.. any acid would work. I just mention SS because it's typically found in the average home brewery and also something we dump a lot of.

 

[RPh_Guy]

something we dump a lot of.

Speak for yourself.

 

[IslandLizard]

Where does your washing machine drain into? Probably not your septic, so use that.

 

[Tom R]

Everything coming from the house drains to the septic system, I believe that's typical in the Puget Sound area.

I like the idea of using star san to counter PBW, I can manage that.
Thanks!

 

[IslandLizard]

I like the idea of using star san to counter PBW, I can manage that.

The acid in Starsan may not be able to neutralize all the alkali in PBW if mixing similar volumes of working solution.

Keep an eye on the resulting pH as an indicator.

Cheap acids are concentrated muriatic acid from the hardware store. I used that to keep my pool's pH in check, when I had one.

 

[kh54s10]

Unless you are brewing every day I would say the amount of PBW going into the septic would be very minimal overall. If it was me I would just go to HD and buy the septic stuff.

I had septic and dumped Oxyclean in it for years with 0 problems.

 

[Horseflesh]

I’m on septic near Seattle and have put PBW down there for years. No troubles yet...

 

[cabron99]

I was experiencing some problems w/my septic so I dug a separate pit for the brewhouse. Gravel, filter cloth, inspection pipe,etc. Might have to neutralize occasionally.