Vertex Puratek RO Unit Questions

[Madreefer]

A while back I got burned on this RO unit from a scumbag store in Abbotsford that is no longer around. Anyways I complained about it and the guy sent me a new membrane. The new one is for 100GPD the one I took out is for 50GPD. So how do I know what my RO unit is rated for? 50 or 100. Also when is it time to change out the filters and DI resin? And are all the cartridges compatible? Since changing the membrane from the 50 to the 100 I seem to have to clean my glass more often and wondering if this is a part of the reason why.