Anyone that has been shopping around for a media based water treatment device has probably asked themselves “How long will this media last and what’s involved with changing it”?
As far as the effective lifetime of softener resin or filter media goes, not even the manufacturer can predict for sure for some very good reasons. First, nobody has any idea how much water is going to flow through a given amount of media day after day. Also, elements in the water can drastically affect the life of the media. If a water softener were treating water with a hardness rating of 10gpg (grains per gallon) with little or no iron present, it would certainly last longer than the same softener treating 10gpg of hardness on a municipal water supply which contains 2ppm (parts per million) of chlorine. The chlorine will shorten the life of the softener resin to a degree. We have discovered softener resin dating back 25 years that was still effectively removing hardness.
The absolute most scientific and accurate way to determine when your water treatment appliance needs a new media bed is to test the water quality every so often. For example, if you are using a softener to remove hardness, the softener is set to regenerate correctly and is not out of salt (or potassium chloride), then your water should contain zero hardness. If you place a hardness test strip under your faucet and it shows 5 grains of hardness and the above mentioned conditions are met, your media bed needs to be changed. The only exception to this rule would be a softener installed with a hardness bleed-through device. Some people prefer a little bit of hardness in their water as opposed to none at all. In this case, disabling the bleed-through device and testing the water would give you more accurate results.
The same method applies for a carbon filter being used to treat chlorine. Your chlorine test strip should indicate zero chlorine so long as your carbon media bed is performing properly. If you note chlorine leaking through, it is time to either step up your filter’s backwash schedule or replace the media bed.
The concept of replacing media is not all that difficult to grasp. The old media needs to be removed from the filter or softener tank, disposed of properly and replace with new media. Replacing softener media is almost that simple. The tank resin tank must be removed from the plumbing and softener system. In most cases, this involves shutting off the feed water supply, removing the water pipes from the system and unscrewing the control valve from the top of the tank. The tank will be full of water so it will be quite heavy. Take care when moving this tank to a suitable location for resin removal. Once the tank is somewhere that the resin media can be poured out of the tank for drying and disposal, pour the resin (and water) out of the tank.
When the resin beads are surrounded with water, they pour quite easily, but once the water has drained off, the resin bed will lose it’s fluid characteristics and stop flowing. At that point it is helpful to have a garden hose handy to spray water into the resin media and pour again. Repeat this until as much resin comes out as possible. The distributor tube (a pipe running up and down the center of the media tank) will come out during this process as well. The distributor tube is not fastened in but merely sits in a depression inside the bottom of the tank. You will want to remove this tube while hosing out the interior of the media tank. Replace the tube when you are done, plug the top end of it so that the replacement media does not get inside of it and finally, add your replacement resin.
After refilling the tank remove the plug (or piece of tape) from the end of the distributor tube before screwing the control valve back on. Re-connect your plumbing and slowly begin pressuring your softener back up with water. Once all air pockets are out of the softener system and it is full of water with equalize pressure, it is a good idea to place your softener into regeneration mode. This will ensure that any dust or debris is flush out of the media bed and down the drain.
A very large softener or automatic backwashing filter requires another consideration. Because softener resin beads are quite smooth, most softeners do not make use of a gravel bed for the bottom of the media tank. This gravel bed is important for filter media because of the coarse surface of typical filter media granules. Without the gravel bed, your filter media will not backwash correctly. So when you pour out the filter media from the tank, the gravel bed will come along for the ride. You will also need to replace that first before adding the replacement filter media.