Re: Excessive usage of water maker membranes

Mark Erdos



So good to hear from you and hope you are doing well.


Thanks for the info on the chlorine test strips. This is an avenue to pursue. We do see lower ppms when we run the water-maker for longer periods and more frequently. But sometimes, like now it doesn’t seem to want to go down and we are in very clean water.


We use a charcoal filter to filter shore water as it goes into the tank. And, I have a double charcoal filter set up for the fresh water rinse. I will check this with some strips.  



With best regards,





Sailing Vessel - Cream Puff - SM2K - #275

Currently cruising - Tahiti, French Polynesia


From: [] On Behalf Of Miles
Sent: Sunday, April 19, 2020 10:32 AM
Subject: Re: [AmelYachtOwners] Excessive usage of water maker membranes


Hi Mark,

I once ruined a set of membranes by putting chlorinated dock water in the boat and then back flushing.  Since then any shore water that goes into the boat first goes through a “whole house” filter that removes chlorine.  To check this, I have test stripes that measure the amount of chlorine in water.  The test kit is sold in tropical fish stores.  My filters are over 10 years old.  I have been told that the more the filters are used, the longer they will last. When I don’t use the water maker much, the TDS goes up toward 300.  When I use the water maker for my total supply off-shore or in a very clean harbor, the TDS goes back down toward 200. 

I agree with the comments.   I also run the water without pressure for several minutes when I turn it on to get all the fresh water from the back flushing out. I agree with Alan that the pressure with fresh water could be damaging.


Miles  s/y Ladybug,  sm216,  locked down in Le Marin, Martinique


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