About Acid Neutralizers

Q. What size should I get?

A. If you have 1 bathroom and there are 1 or 2 people in the home, the 1.0 cubic foot models (which come with 110 lbs of calcite media) are best. For most homes with over 1 bathroom up to 3 bathrooms and 1 to 4 people in the home, 1.5 cubic foot model systems are best. If you have a larger home or large family and use a lot of water you can get the 2.5 cubic foot model. One important consideration is the backwash flow rate. Your well only needs to flow at 5 gallons per minute to backwash the 1.0 and 1.5 cubic foot models, where as your well must produce 10 gallons a minute at least, in order the 2.5 cubic foot model to work.


Q. What if I don’t know my well’s flow rate?

A. It is very easy to find out! Click here for easy steps to measuring your well flow rate in gallons per minute.


Q. What maintenance is required?

A. There is very little maintenance. A quick once per year refill of the tank with calcite is all that is usually required. Periodically, and depending on raw water pH and the amount of water used, additional mineral is easily added to the filter tank. This is typically once a year for the average home. In some cases, the calcite or calcite-corosex blend is added twice a year depending on the pH and amount of water that is used through the neutralizer filter. Because our neutralizers have a top fill plug and a bypass valve it easy to add the mineral. Just put the neutralizer on bypass, release the pressure by manually backwashing the neutralizer filter, and unscrew the top plug using any medium sized channel lock pliers or crescent wrench (available at any hardware store). Stick a tape measure into the fill plug hole and determine if the calcite mineral is less than 2/3rds full. If it is, simply add more calcite until the neutralizer tank is 2/3rds full again, re-install the fill plug and backwash the neutralizer. This entire process takes about 20 minutes.


Q. Does the neutralizer systems come with the media, or do I need to order the calcite separately?

A. Yes it comes with the calcite, it is included in the price. You can get a discount upon check out if you want to order additional calcite or calcite corosex blend, but you won’t need it for six to twelve months at least.


Q. How much does it cost to ship the calcite neutralizer to me?

A. Nothing, it is included in the price.


Q. I have heard that the calcite (or calcite-blend) neutralizers will make my water hard, and then I will need a water softener. Is this true?

A. The calcite and calcite-blend neutralizers work by adding calcium to the water, and it will increase the calcium hardness of the water, making the water ‘harder’. However, most acidic well water is soft to begin with, and after passing through the neutralizer, will be harder, but still not hard enough to warrant a water softener. Generally if the water is less than 170 mg/L or 10 grains per gallon, most customers can avoid having to use a water softener. If your water is 3 grains/gallon to begin with, after the neutralizer it might be 5 to 7 grains per gallon, as the neutralizers will add 3 – 4 grains per gallon on average. You can always add a water softener later if you find you want one, but we generally do not recommend a water softener be installed. If you are having white spotting on fixtures and you want a water softener, you could install them both at the same time, but its better for the elimination of copper corrosion, if you wait 3 – 6 months to give the neutralizer a chance to stop the copper corrosion before adding the water softener.


Q. What are the dimensions of these acid neutralizers?

A. The 1.0 cubic foot size has a diameter of 10″ and a height of 51-3/8″. The 1.5 cubic foot size has a diameter of 10″ x 61-3/8″. The 2.5 cubic foot size has a diameter of 13″ x 61-3/8″.


Q. Do you sell 2.0 cubic foot size neutralizers?

A. Yes. Please call our office if you need this size. The 1.0, 1.5 cubic foot and the 2.5 cubic foot models are the best sizes over-all and fit almost all residential applications though.


Q. Is there a pressure loss through the system?

A. Properly sized, the system produces a very low pressure drop at service flow rates, usually around 3 to 5 psi and is not noticeable. At the peak flow rate, or the absolute maximum flow rate the control valve can allow, which is around 27 gallons per minute for the WS1 Clack control, there would be a pressure drop of 15 to 20 psi. However, for most typical homes with 1 to 3 bathrooms and wells with flow rates of 10 – 20 gallons per minute, and the average flow rate of 8 gallons per minute, (a shower running, washing machine filling, or toilet flushing at the same time for example) the pressure drop is hardly noticeable at around 3 – 5 psi. However if you have a very large home with 4 or more bathrooms, and a larger family, or commercial application with special requirements, we have other larger sizes available so contact our office for more details.


Q. I have 1-1/4″ (or 1-1/2″) piping, do you offer larger sizes?

A. Yes, these same systems come with 1-1/4 and 1-1/2″ pipe size for an additional charge. We also have many larger sizes not listed for very large homes or for businesses etc. Please contact our office with your particular requirements.


Q. How do acid neutralizer filters work?

A. Acidic neutralizers slowly dissolve the calcium and/or magnesium media on contact as the water flows through the filter, raising the pH of the water and increasing the alkalinity. This eliminates the effects of corrosive water, eliminating the effect of acid well water, and can help to prevent corrosion of piping and fixtures. They contain either 100% calcite, or a blend of calcite and corosex. Calcite is a natural calcium mineral that is mined for this purpose. Corosex is a trade name that is a natural mineral product which contains magnesium oxide. Also read our guide How to Treat Acid Well Water.


Q. I have heard of “magnetic acid neutralizers”, do those work?

A. A magnet or a catalytic gadget will not take the place of a calcite acid neutralizer tank. These do not raise the alkalinity or change the water chemistry, and we do not recommend them to correct corrosive well water.


Q. Do you sell the Fleck control valves for neutralizers?

A. Yes – we do offer Fleck neutralizers for those customers who specifically want a Fleck control.


Q. Do you sell neutralizers with Fleck 5600 controls?

A. No we don’t recommend the Fleck 5600 control. It is an economy model backwash control and unlike the other models, there is no way to adjust the length of the backwash time.


Q. Do you offer manual backwash neutralizers? I don’t it want to backwash automatically, I want to do it myself manually.

A. Yes, we offer the Fleck 2510 manual backwash neutralizers. (Click here). We have them in both standard calcite for pH 5.0 to 6.0, and calcite-blend containing Corosex for pH below 5.0. However, one problem with the manual backwash neutralizers can be that the neutralizers end up being backwashed very infrequently. We often hear from customers who set up or purchased manual backwash neutralizers over the years, and then discovered the filter media had partially solidified. The calcite and particularly the calcite-corosex blend neutralizer media can start to form solid blocks and become partially solid if they are not backwashed at least once every two weeks. Generally its better to get an automatic control but for many people off-the-grid, or those who do not have electrical power nearby the manual backwash Fleck 2510 neutralizers are a good option.


Q. Do you offer any other sizes of pH neutralizers?

A. Yes. We have sizes up to 1200 lbs or 12 cubic foot, so contact use if you need a quote for a commercial or other special need.


Q. I have a very small space the neutralizer needs to go in and I do not have the height required. Do you offer smaller tanks that have a lower height?

A. Yes. Please contact our office with your height requirements.


Q. Why not use an up-flow neutralizer, which does not have a backwash control valve?

A. We have these too and you can deduct $150 off the price for an upflow however we do NOT recommend them. Many people call us regularly with problems they are having with the upflow neutralizers. The biggest problem is channeling where the water flows up the side of the tank and the media does not dissolve properly and forms balls or solid blocks of calcite or corosex inside the tank. It is better to use a backwash control because the media is periodically flushed with water (usually once every one or two weeks) which keeps the media in good shape and prevents channeling.


Q. I notice in your diagram that you show the neutralizer after the pressure tank. Why can’t I install the neutralizer filter before the pressure tank?

A. All backwashing filter systems (such iron filters, softeners, any type of backwash system) must be after the pressure tank because when the backwashing filter goes into a backwash, say at 2am on a given night, there must be pressurized water entering the inlet to the sediment filter, in order for it to backwash properly.

If the pressure tank were after the system, and the filter system went into a backwash, the well would not turn on because there is a check valve before the pressure tank to prevent the water from being discharged back into the well, and the pressure switch would not register that the pressure had dropped and the pump must turn on. If the check valve was down the well, or on the other side of the sediment filter, say on the inlet to sediment, when the sediment filter went into a backwash, the water would enter the sediment filter through the outlet on the sediment, not the inlet, causing it not to backwash and causing other problems.

The pressure tanks have the in and out pipe (typically one pipe on captive-air pressure tank) on the direct bottom of the pressure tank, so usually no sediment will build-up in the tank. But in any case, there is no way to use a backwashing filter before the pressure tank. Also, say you wanted to use a cartridge filter instead of a backwashing filter system, and you placed a cartridge type filter before the pressure tank. After a while if this filter became plugged up, your well would not be able to shut off properly because the pressure on the inlet side of the filter from the well is much higher than the pressure tank pressure. This will cause the pressure switch to rapidly turn on and off and eventually cause damage to the well pump motor.

Generally it is NOT a good idea to put any type of flow restriction such as a filter cartridge or backwash filter before your pressure tank and it is not necessary in any case because modern pressure tanks are lined with a special coating to prevent corrosion.


Q. Regarding the drain line for the backwash, can I run that with a garden hose and use it to irrigate my garden?

A. Yes, the backwash line can be run with a garden hose. In some areas local codes prohibit the re-use of backwash water from filter systems or water softeners.


Q. Can I run the drain line up and over the top of the neutralizer filter? My drain is in on the ceiling above the where I want to install it.

A. Yes it is no problem to run the drain line up several feet higher than the top of the neutralizer tank, because the neutralizer filter backwashes under line pressure from your pressure tank and well pump system.


Q. Do you ship to Canada, Alaska, Hawaii, or internationally?

A. Yes, for an additional charge but we do ship regularly all over Canada, Alaska and many parts of the world at a discount over the actual freight cost. Please email us with your postal code and we will quickly give you the cost.


Q. Is Corosex different than calcite?

A. Yes, it is a much more powerful agent than calcite. On a per weight basis, magnesium oxide (sold under trade name Corosex or Flo-Mag, can neutralize five times more acidity than can calcium carbonate. Unlike calcite, which will never raise the pH above 7.0, corosex is powerful to the point where it can over-correct and raise your pH too high- which is why it is used in small amounts. Getting your pH anywhere in the range of 7.0 to 7.8 or so is ideal.


Q. Does corosex cost more than calcite, does it last as long?

A. It does indeed cost more than calcite- for example, we sell 50 lbs of calcite for 79.00, whereas 37.5 lbs of corosex sells for 89.00. It tends to last about as long as calcite, but as you’re using less in the system, it may sometimes need replenishing a little sooner than the calcite. We include a free pH test kit so you can monitor the effectiveness of the system over time, and use that as a basis to determine whether you need to add more corosex or not.


Q. What is pressure drop for these neutralizers?

A. It’s pretty minimal- around 3 to 5 PSI for the Fleck 7000 1.5 CF system.


Read our report: “How to Treat Acid Well Water” using calcite neutralizers
Read our report: “How to Treat Copper Pipe Corrosion”
See our page on Acid Well Water and Low pH

  • Clean Water Systems & Stores, Inc., Water Treatment Equipment,Service & Supplies, Santa Cruz, CA