Add CYA before or after changing cartridge filter?

[poolnoobgrandma]

It's time to change our cartridge filter, and we also need to add a couple of pounds of CYA. I just noticed that the label on the CYA says make sure your filter is clean. Should we dump the cya in (sock method) let it run for a few days, and then change our filter? Or change the filter now and then add the CYA? Note: the filter was cleaned recently but it's making a terrible vibrating noise from time to time so we figured it would be a good time to change the filter.

 

[magiteck]

I would change the filter before. Some not-fully-dissolved CYA can get caught in the filter, and will then dissolve over several days. If you change the filter after, you'd be throwing that CYA away.

No harm in adding CYA with a new/clean filter.

 

[elwood58]

You will want to avoid filter change/cleaning for at least seven (7) days after the addition of CYA.

 

[mknauss]

It's time to change our cartridge filter

How old are your filter cartridges? Unless the media is compromised, they should last many years. At least 5, potentially 10.

 

[poolnoobgrandma]

How old are your filter cartridges? Unless the media is compromised, they should last many years. At least 5, potentially 10.

I don't disagree with you. Last year we had to replace our filter because we had had a lot of tree work done, and the sappy sawdust pretty much did in the filter. Our filter started making a loud vibrating sound, and based on information here and elsewhere, we thought it might be the filter, but I also called the PB because some folks said they got a warped housing replaced under warranty. PB said filters only last a year (or, for any problems try changing the filter, if it's over a year old), and some googling made it sound like the life could be one year (very hard to get an estimated lifetime on the Hayward site) so we bought a new filter. FWIW, we put a soda keg o-ring at the top of the filter, and the vibration has stopped (for now).