Catit Flower Fountain Filters - replacements, new fountain alternatives

Been using the stainless steel Catit flower fountain for over 2 years now and while my cat has no issues drinking from it (which is a huge plus), their official replacement filters have noticeably gone down hill within the last 12-18 months and I can’t trust spending any more money on a product that is highly questionable. Just like most negative reviews on them I too have seen the foamy substance, reddish/pink residue, etc.

I’ve always wiped down the the fountain and replace the water completely every few days. Fully cleaning it and the pump each month before a new filter. At first I thought maybe the water at my place was starting to be the culprit but after seeing the reviews match my experience it’s clear it’s the filters and their poor quality/performance. My cat, who is only a little over 3yr old, has had some unexplained ongoing health issues that have started since ~June of last year that I’m beginning to wonder if this has been attributing to that. Have had plenty of visits to the vet for these issues but still been a mystery.

Long story short I am now considering a replacement fountain or some alternative filter replacement. I can’t say I trust Catit’s own filters anymore since the last 12+ filters have done this. Ideally I’d like to keep using the fountain simply because it’s familiar to my cat and she’s comfortable with it but looking for a filter replacement that isn’t junk, or even a DIY option suggestion.

Open to other fountain options too but only if their filter performance has been proven to be of quality and not subpar like Catit’s have proven to be.

Any ideas out here?