Waterdrop AP431 Whole House Scale Inhibitor, NSF/ANSI 372 Certified, 3 Pack

This Waterdrop AP431 replacement cartridge is an excellent alternative to the OEM Aqua-Pure AP431 filter. It fits my whole house water filter system perfectly with no modifications needed—drops right in just like the original cartridge. The water quality after installation is noticeably improved with better taste and clarity. No chlorine taste or odor, and the flow rate is excellent. The filtration performance seems just as good as the original filters but at a much better price point. The build quality is solid with good materials and construction. The threads sealed properly without any leaks, and the cartridge housing feels sturdy. Installation was quick and straightforward—just standard filter replacement procedure. I've been using these Waterdrop replacements for several cycles now and they consistently perform well. The longevity seems comparable to OEM filters, making them an even better value. No decrease in water pressure or quality over the filter's lifespan. For anyone looking to save money on replacement water filters without sacrificing quality, these Waterdrop cartridges are the way to go. They work just as well as the brand name filters at a fraction of the cost.

Dependable quality & service.

I have started purchasing and using these replacement cartridges for all of my Aqua-Pure descale installations. I am a plumbing contractor, so I perform annual maintenance service to all my customers that have tankless water heaters. This includes replacing the cartridge when I do the descale operation using a recirculating pump and vinegar solution (many videos on youtube on how to do this). I Install the stainless steel tee, which is supplied with the complete scale inhibitor kit (available on Amazon), on a horizontal section of the cold water pipe downstream of the shut-off, before the flexible corrugated connector on the inlet to the tankless water heater. I also use 3/4" brass or stainles steel nipples (not galvanized steel!) on either side of the tee, but typically on the outlet for the female union of the flexible connector. These cartridges have proven as reliable as the Aqua-pure that I normally use, at a reduced cost. These are NOT filters, as many people assume. They are in-line water treatment system which uses polyphosphates to inhibit hard-water scale buildup. I have used this system for many years to protect the internal heat exchange chamber on all of the tankless water heaters that I install for my customers. You could also install these on the cold water line coming into your house as a whole-house water treatment, but you would probably want to replace them more often due to increased use. I hope this info has been helpful - cheers!

quick ship, good fit

As ordered. Works like it is supposed to and delivery was great. Priced fair.

Works great! I have it hooked up on a demand water heater with well water. 3rd year in a row with this filter. Take your time threading it on since they are plastic threads. I have no issues with leaks.

Works very well.

Ordered AP431 and got WD-W65 it says replacement for AP431. Vendor should correct the description and pictures. Also the cartridge is not full, the beads will rattle around when shook up and down. It is the same as the one I replaced, it is also a WD-W65. I use this in the supply line to my motorhome and it does a good job of keeping the lime scale down. It will not remove calcium, lime, or hardness ions or copper, magnesium, lead or other metals, it just sequesters or contains them so they will not precipitate out and cause scale. I got this motorhome 3 years old and the shower valve has so much scale in it, it sounded like it had sand in it. I replaced the valve and added the AP431. No problems for the past 3 years. I just built a little stand for it with 2.5 inch PVC pipe so I can keep it upright as it is supposed to be. It shows in the pictures you can use it for the whole house. I do have one question and that is how safe is it to drink and bathe in water that has polyphospates in it to sequester all the hardness minerals and what does it do in the body. I have asked and not gotten any concrete answers.

Just as good as the brand name stuff