Penair RFC Filter

I am interested in buying an Ametek Big Blue RFC cartridge.
If I buy 3, how long can I keep the 2 extra cartridges before I use them?
Is there an expiration date on these cartridges?

Also, for a household of 4, how frequently do I need to replace the RFC-20BB?
Or, how do I know when it’s time to replace it?

1. It would last quite a while if stored in a cool dry place.
2. Frequency of replacing really depends on the quality of water treated. There’s no set time for this.
3. When to change: Some would say once every 6-12 months, but again, there’s no set rule for this. If water flow becomes lower then usual, or the taste gets bad, you may wish to replace it.

There are quite a few filters in the RFC series. There’s RFC-20 155065, RFC-BB 155141 and RFC20-BB 155247

What’s on your mind