Has anyone added an extra membrane to an RO?

I have a small (10”) 300 GPD RO from pure freedom. I bought it as they have been out of stock of 450 GPDs for ages. As the description said it came with 3 x membranes I assumed it would come with 3 x 100 GPD membranes and therefore I could replace the membranes when the time came with 150s to make a 450 GPD unit. However, it arrived with only two membranes and it transpires that they are two x 150 GPD. So to upgrade it I will need to add another membrane. Has anyone had experience of doing this and is it easy enough to just hook another one on there? Is there anything I need to know before doing this?

Should be very simple. One thing to note is how is your waste controlled? If it's by a fixed restrictor you might need a different one.

Simplest method is to contact pure freedom explain that you bought the 300gpd RO with 2 membranes and you want to add a third to make 450gpd. I am sure they will sell you all you need.

ched999uk said:

Should be very simple. One thing to note is how is your waste controlled? If it's by a fixed restrictor you might need a different one.

Simplest method is to contact pure freedom explain that you bought the 300gpd RO with 2 membranes and you want to add a third to make 450gpd. I am sure they will sell you all you need.

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It’s one of those quarter turn levers.

I contacted them saying it doesn’t fit the description and they said an extra one can be added. I asked for a link to the stuff I need to buy but no response as of yet.

It looks simple enough but want to do it right first time with out cocking it up!

brianbadonde said:

It’s one of those quarter turn levers.

I contacted them saying it doesn’t fit the description and they said an extra one can be added. I asked for a link to the stuff I need to buy but no response as of yet.

It looks simple enough but want to do it right first time with out cocking it up!

Click to expand...

https://ro-man.com/?product=membrane-upgrade-kit

As @ched999uk stated waste restriction will change if you have a fixed inline restrictor.

Ro-man also sell them specific to the r/o. I would be inclined to go to a 1/4" gate valve so you can control waste more accurately. However, using a gate valve will not be as aesthetically pleasing.

I upgraded my 275gpd to 450gpd by just changing the membranes and inline restrictor. The restrictor was preset to 3 waste to 1 pure - not ideal to save water.