The Echotec uses standard 2.5" x 40" membranes. Wateranywhere sells them for under $200. Specs like this: 2.5"x40" | 700 GPD | 99.6% Salt
Rejection | Watermaker Seawater RO
Echotec has been very unhelpful with my system, they keep charging
me $80 for a set of brushes
-- and the brushes
they send me just fall apart in a few days. Echotec can't tell me if there's a special way to install them (they don't come with a uniform curve). No instructions. My existing brushes are short, don't work
very well, but at least they don't fall apart!