Which cartridge fits this filter? Or another question, what kind of filter is this exactly?

Can I also use this model with salt water? Or does something rust too quickly?

I would like to transport the package(s) in the car. Hence the question: How many individual packages ? Dimensions and weights ? Other questions: Are the hoses from the pool to the filter pump included in the delivery? is there a cover for this pool? if so, article no. and price?

After 2 or 3 summers in the sun, the film has become brittle and has holes. Where can I get a replacement film? I don't want to buy a whole new set and have to throw the rest away.