Algae in water filter

[The Blur]

I have a 1" water main. 1" whole house filter. (actually 2 filters in parallel). Paper element. Blue opaque housings. Changed the filters today. (1 year old). Both filters were covered in slimy algae. Why ?
I've been drinking it, never tasted bad. But what is the problem?
Why algae? They are paper sediment filters.

 

[Reach4]

I have a 1" water main. 1" whole house filter. (actually 2 filters in parallel). Paper element. Blue opaque housings. Changed the filters today. (1 year old). Both filters were covered in slimy algae. Why ?
I've been drinking it, never tasted bad. But what is the problem?
Why algae? They are paper sediment filters.

Are you saying you have city water? If so, I would have a talk with the water department/company. Residual chlorine or chloramine should keep algae from growing. There are paper strips you could buy that can measure the residual chlorine or chloramine. When you say algae, I presume it was green. If it was dead, I would still maybe talk to the water company.

You don't have another filter before the cartridge sediment filters, do you?

If you have a well, say so.

 

[Sponsor]

 

[The Blur]

City water. The more I look at it, I don't think it's algae. I think it's slimy rust. It's not green... It's dark brown, but it's slimy, and obviously still wet.

 

[Reach4]

Are the two filters in series? If so, it is very troubling that both elements have what appears to be the same stuff on them. If it was dead stuff, you would have expected the second one to look much different. Is this maybe a multi-story building with its own water tank? If the filters are in parallel, then having the two cartridges have the same thing on them makes sense.

I would

Ask your water department why you are getting that slime on your elements.
Find out if your water department uses chloramine or chlorine.
I would get the appropriate test paper strips on order. I hope they use chlorine.
I would switch from cellulose filter elements to polypropylene cartridges. Cellulose is good for treated water, but your water is suspect IMO.​