Hi Doug. So I've disassembled the whole thing. Undoing Champ housing nearly made me pass out but I got there. No dirty water anywhere, below is the pic of the membrane but not sure how much can be told from that.The only thing that will reduce the flow in your membrane if it’s blocked due to dirty water coming in. This is normally caused by dirty mains water.
You can normally unblock it if you flush your membrane for a good hour or so.
If that fails then the membrane may be blocked.
A tell tale sign is when you open the membrane housing and dirty water comes out.
Reassembled it and its still low ppm but very low flow. No change. Removed filters as you mentioned before and flow is the same or even worse actually. I can't increase flow whatever I do, so membrane must be bust I guess?
As I asked in my last post, any idea on what could have caused this and how I can avoid it? My water from tap is between 350 and 500 depending on the day. And as I've mentioned I forgot to change carbon filter for 4 to 5 months.