Watermaker layup and pickling: doing it right

Membranes hate two things: drying out and sitting wet with untreated water. If your boat is going to sit for more than a couple of weeks without running the watermaker, pickle it.

Short-term (up to 2 weeks)

Automatic fresh-water flush is usually enough — as long as the flush is actually working. Confirm the solenoid opens and the flush pump runs.

Long-term (2+ weeks)

Circulate a manufacturer-recommended biocide (sodium metabisulfite or propylene-glycol based, depending on system) through the membrane. Cap the intake and product lines so nothing evaporates.

Recommissioning

Flush the biocide out fully before making drinking water, and check salinity for the first 20–30 minutes of operation.