New RO Membrane water

Hi All,

I recently replaced my RO membrane on my Ro/DI unit. After installation I let it run for a few minutes to flush out anything that could be in it. I recently read from a couple of sources that I should have thrown away the first five gallons from the new RO membrane because there may be anti-microbial treatment in the membrane.

Can anyone tell me if its safe to use this water in my reef tank or do I need to dump it and start over?

 

You should send the first 3 to 5 gallons to waste. Bypass or remove the DI filter at this time also so you don't load it up and exhauste it prematurely too.

Dry membranes such as GE Water and Dow Filmtec are treated with antimicrobial agents or preservatives and need to be flushed to remove such and to season the membrane fabric.

A TDS meter on the RO only water should tell you if the membrane is properly flushed, the TDS should drop into the 96-98% rejection rate range and stay there when flushed. When its at its lowest after 3-5 gallons it is good to use and you can hook the DI back up.

 

RO Membranes must be flushed

Definitely flush your Filmtec or Osmonics membranes. The do have some anti microbial agents for the dry ones and formaldehyde for the wet ones. Visit easternro.com for your replacements.