Just Say No to Pot Perm (Potassium Permanganate).
What’s the solution to smelly water or staining water? In our humble opinion, it’s not potassium permanganate, otherwise known as Pot Perm.
If you have rotten egg smell or staining from iron or manganese in your water, you may often hear that manganese greensand with a Potassium Permanganate (Pot Perm) regenerant is the answer. If you are talking about a residential home, we respectfully disagree.
What is Potassium Permanganate?
Potassium Permanganate (Pot Perm) is a non-organic chemical compound, which is actually a salt.
Ideal Conditions
The water treatment industry has used manganese greensand filters with potassium permanganate to filter particles and clean the water for years. These filters offered an economical approach toward achieving at least the minimum treatment results required.
The beauty of manganese greensand is because, under perfect conditions, it appears to be a one piece fits all system. The perfect conditions are a combination of pH, flow rate and the chemistry of the elements being removed.
Real Conditions
Optimal conditions are rarely met when it comes to pot perm and greensand filters. Water chemistry parameters must be within a specific narrow range. Since conditions vary, performance can often be slightly below what is required to meet your needs. The media used in these filters is very heavy. Some homes are unable to maintain the pumping flow rate required to adequately backwash (clean) greensand.

Potassium Permanganate water
Magenta Pink Water Staining
The problem may arise immediately. It builds up over time. This can lead to small amounts of potassium permanganate left behind in the media bed, which begins to build up.
Potassium permanganate is died purple so the homeowner is alerted to a failure in the system. The buildup creates a pink water condition as it dissolves later. A severe pink or purple water condition may result any time the pump rate drops below the rate required for the size of tank installed.
Potentially Hazardous Chemical
Potassium permanganate is a potentially hazardous chemical. It is sticky and may eventually gum up the valve used in the system, causing the valve to fail, even if maintained. This failure can result in a flood of toxic material. This can stain the basement floor, damage personal property and furnishings, and possibly cause harm to a person in contact with the material. For your reference, you can check out the MSDS Sheet for Pot Perm.
Not Good Enough For Secondwind’s President? Not Good Enough For You.
For years Secondwind was happy to install manganese greensand in homes that fit the required criteria. However, over the years, this lead to a nightmare of customer dissatisfaction. Problems included manganese that refused to oxidize and filter and ferrous iron that was stubborn and would incompletely oxidize and then pass through at higher flow rates. We also saw hydrogen sulfide that would still be present sometimes causing continued rotten egg odor. We had only intermittent success with arsenic removal. And then finally, the purple floods.
One by one we’ve removed almost all of the manganese greensand systems we ever installed, including one in our President, Christine Fletcher’s, home. In each case, we worked with the customer because we wanted to regain their satisfaction and loyalty after this product disappointed. Christine remembers when a customer had a potassium permanganate flood that damaged a wooden rocking horse she was saving for her grandchildren. It was heartbreaking. We simply refuse to put our customers and their belongings at risk in this way any longer.
The Solution
The solution to this problem is to design a multi-part water treatment system tailored to your water chemistry and home. By investing more now, and dividing your treatment up into pieces, you can have years of great satisfaction from a reliable water treatment system. Contact us today to learn more.