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Neutralizer 2510 Manual Calcite 1.5 CF


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Neutralizer 2510 Manual Calcite 1.5 CF
Code: NF003840
List Price: $1,134.40
Your Price:
Shipping Weight: 181.00 lbs.
Quantity in Basket: None
Manufacturer: CWS
Manufacturer#: 2510MFB-10T-NEU

Product Documentation: 
Download Installation Guide

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Wish List


  • Neutralizer 2510 Calcite Manual Backwash 1.5: includes 3/4 or 1 inch pipe connectors; by-pass valve; 1.5 cubic foot of Calcite filter media; 10 x 54 inch filter tank with top-fill plug; and Fleck Manual control valve.Uses the higher quality, more expensive Enpress tank with Vortech distributor which allows the neutralizer media to be backwashed at lower flow rates with less water, saving water and energy.
  • All the filter media you need for the system is included.
  • Eliminates acidity in the pH range of 6.0 to 6.9 by slowly dissolving Calcite (calcium carbonate) into the water as it flows through the filter.
  • Depending on pH and service flow the Calcite bed will need to be replenished periodically with more Calcite.
  • Filter tank is NSF certified one piece seamless polyester construction for long life.
  • Max pressure recommended is 100 psi.
  • Maximum water temperature recommended 100F.
  • Rugged Fleck 2510 manual backwash control lasts for many years.Time-tested hydraulically balanced piston seal and spacers provide years of trouble-free service.
  • Non-corrosive high-tech material construction.
  • Manual control valve is easy to operate; just move lever to move to a backwash and then rinse position.
  • The recommended maximum flow rate for best performance is 7.0 gallons per minute but peak flow rates of up to 10 gallons per minute are possible.
  • The backwash flow rate is 5.0 gallons per minute.


  • Filter tank diameter: 10 inches
  • Filter tank height: 54 inches
  • Height including control valve: 61 inches
2 different Fleck backwash control valves to match your needs. Each neutralizer comes with top dome hole to make it easy to add more calcite or calcite/corosex blend later.
2510 Series 7000 Series    
neutralizer tank top 2510fleck 7000 neutralizer top  
Not sure of your pH?

Click here to get a FREE test kit mailed to your house. Test for iron, pH, hardness and more!
Which one to use? Pipe Size # of Bathrooms
2510 Series 1.0 Cubic Foot 3/4" 1
2510 Series 1.5 Cubic Foot 3/4" 1 to 2.5
7000 Series 1.5 Cubic Foot 1" 2 to 3
7000 Series 2.5 Cubic Foot 1" 2 to 4
Neutralizer filters work by dissolving natural calcium and magnesium into the water to raise the pH to safe levels. Unlike many neutralizers online our neutralizer filters are specially designed to make it easy to add more mineral each year. Don't purchase a neutralizer that will be hard to service!

Neutralizer Filter Cut-Away
Each neutralizer comes with top dome hole to make it easy to add more calcite or calcite/corosex blend later. These automatic acid neutralizers use the famous Fleck Backwash Control Valves for years of trouble-free operation!
More information on acid neutralizers:
Large Capacity: Won't restrict pressure or flow unlike cheaper uplfow neutralizers or converted water softeners neutralizers commonly found online.
neutralizer control valve rear
Fully Automatic: Sediment and particles are automatically flushed from system, and filter media cleaned! No monthly maintenance. Reliable Fleck backwash control valve for long life and low maintenance.
Large Media Bed Means Long Life: Large size means you don't have to add more calcite mineral on a monthly basis. In most cases, additonal minerals is added once per year.
Economical Operation: Additional calcite mineral costs on averages $ 30 to $69 per year for most families.
10 year warranty on filter tanks, 5 year warranty on control valves. Uses Fleck control valves - the industry standard for many years of trouble-free operation!

Frequently Asked Questions about Acid Neutralizer Filters:

Q. What is the difference between the Fleck 2510 and Fleck 7000?
A. If you have over 2 bathrooms and a higher peak flow rate demand though, it is better to get the Fleck 7000 as it has less pressure drop and offers a higher flow rate than the Fleck 2510. If you have one or two bathrooms, use the Fleck 2510 1.5 cubic foot. If you have 1 bathroom with low water use, you should use the Fleck 2510 1.0 cubic foot.

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 additonal 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. Do you ship to Canada?
A. Yes, for a an additional charge but we do ship regularly all over Canada.

Q. I have seen some other neutralizers online that don't have automatic backwash controls called 'Up-flow Neutralizers". Is there any reason not to use these?
A. The backwash control valves we offer use very little electricity, and you can install it and forget it except for a once per year maintenance to add more calcite. If you do want a manual backwash control though,we do have them so contact us for the price. We don't recommend up-flow neutralizers for homes unless a filter is installed before and after the neutralizer, which creates more maintenance and more trouble in the long run.

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 5 psi. The Clack WS1 has a better flow rate with less pressure drop than the Fleck 2510.

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 chemistries, 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. 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. In place of the Fleck 5600 we recommend the Fleck 2510. However, if you want to replace an existing Fleck 5600 neutralizer please contact us as we can order it for you.

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. I see that some neutralizers use gravel in the bottom of the tank, but your neutralizer does not. Why is gravel used and why doesn't your neutralizer require gravel?
A. Gravel was used in standard neutralizers to prevent the media from clogging the bottom distributor screen, and to allow the water to disperse evenly. Our neutralizers use the Vortech tank with special built-in distributor that has many times the area that the standard distributor screen requires. No gravel is needed and the Vortech distributor disperses the water much more evenly. Less backwash water is required since the distributor screen covers the entire bottom of the tank, instead of the smaller distributor located only in the center of the tank with gravel.

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 commerical 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. Note that the smaller tanks are also narrower in diameter and do not hold as much calcite media, so they may not be large enough to properly neutralize the pH. Generally 1.0 cubic foot with a 10" x 44" tank and an over-all height of 51-1/2" is a good minimum size to get for a residential application.

Q. I sometimes get a lot of sediment in the water after a storm.  Is there anything to gain by installing cartridge-type sediment filters before and/or after the neutralizer (possibly extend life of neutralizer, additional filtration, or having smaller particles filtered out)?
A. Yes, you may want to install a big blue filter before the calcite neutralizer to help in trapping added sediment  and prolong the life of the control valve.  However, the control valve on the neutralizer is mostly affected by grit or sand, not fine sediment.   Sometimes its best to put a filter strainer before the neutralizer to take out large sediment, and a 5 micron big blue type 1” filter housing, after the neutralizer.  The calcite is not affected by fine sediment, as long as it can backwash once a week.

Filter Strainer 1”  100 mesh   $59
Great for Pre-Filtration for all automatic filter and neutralizer systems

Pentek 'Big-Blue" 5-micron whole house filters 1" inlet/outlet from $89:

Q. Why not use an up-flow neutralizer, which does not have a backwash control valve?
A. 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, sediment or iron fouling of the calcite, and the formation of balls or solid blocks of calctite or corosex inside the tank. If you use an up-flow neutralizer with a Vortech type tank it will help minimize this problem with the upflow neutralizers. However you do need a screen inside the neutralizer, or a filter after the neutralizer to prevent calcite fines from entering the downstream piping. Our up-flow neutralizers come with this screen built-in, however, if your water has any iron or bacteria in it, this screen will need to be cleaned periodically. Upflow neutralizers do not offer any filtration or sediment removal like standard backwash neutralizers afford, and the media inside the upflow neutralizer can become fouled if there is any sediment, iron, manganese or sulfides in the water, which does not occur with backwash types. Generally we have found backwash neutralizers allow the calcite media to dissolve over time more evenly and are worth the extra cost and small amount of backwash water required. Backwash type neutralizers work better because the media is periodically flushed with water (usually once every one or two weeks) which keeps the media in good shape and prevents channelling.

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 a 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. What is the warranty?
A. It comes with a 10 year warranty on the neutralizer tank, and a 5 year warranty on the control valve. Click here for warranty information.

Q. What if it doesn't work? Can I return it?
A. Yes. It can be returned within six months if it doesn't work.