[m40doug]

I inherited an Aqua Pure Filter. It was white to red. I replaced it and it's black to white (I think) or white to black. Does it go to red ? When should it be changed? Thanks Doug.

[rscardigno]

I can't tell from your question what type of filter you have. Do you have the model number of the filter that you replaced?

[m40doug]

The box says RF-9999 and it fits all PUR water filter systems (I guess thats not aqua pure after all)

[Roxanne]

Cartridge should be replaced every 100 gallons or 2-3 months depending on usage.