I have a 17,000 gallon chlorine-sanitized pool. We have a Jandy filter with four (approx) 4' cartridges. I don't recall the model number of the filter. We also have a variable speed pump, which runs a bit slower than the single-speed pump we had a couple years ago.
About how often are we supposed to replace the filter cartridges? I clean mine every few months, but they are starting to look nasty. I've had the pool since 2008, and I last replaced the cartridges in 2012.
Thanks in advance for your assistance.