[Lee GLS]

I changed my pre filters today for the first time, they are 6 months old, but they don't really look like they needed changing, does this look like it still had some life left in it?



It's only brown half the way through the filter.

[Steve Sed]

I had a problem a few weeks ago where I could no longer get 0 tds. My filters didn't look as bad as yours, but changing them sorted it.

[mikecam]

its essential to change them regularly, you done right. A thing you can't see in filters is chlorine and its important to get it removed. So yes, if you're making a lot of water i'd chage them every six months irregardless what they look like.