RO/DI Kit Install it after the water Softener or before it?

[makoshark]

Hello, I'm setting up my first reef tank. I just bought a RO/DI kit and I read somewhere that I didn't want to use softened water for my salt tank due to salt ions being exchanged in the softening process giving inaccurate hydrometer readings. Does this hold true if I'm deionizing the water? Can I extend the life of the membranes if the water is softened prior to RO and DI?

 

[AF Founder]

Hello, I'm setting up my first reef tank. I just bought a RO/DI kit and I read somewhere that I didn't want to use softened water for my salt tank due to salt ions being exchanged in the softening process giving inaccurate hydrometer readings. Does this hold true if I'm deionizing the water? Can I extend the life of the membranes if the water is softened prior to RO and DI?

What you want to do is to add the salt to the RO/DI water. You will not need to use a water softner. It is very important that you add the salt to the prepared water, not add the water to the salt. Adding water to the salt will cause some elements to precipitate.

 

[danmhippo]

If your house already has water softener, then you should install the RODI after the water has been "softened". This will also extend the RO cartridge life.

It is very important that you add the salt to the prepared water, not add the water to the salt. Adding water to the salt will cause some elements to precipitate.

This is very important. Simple concept, but not many realize that at first.

 

[makoshark]

Guys, Thanks for your opinoins. Now that I have posted it I realize that I'll end up using softened water after all. I live in a cold climate and I'll have to raise my source water to 70 degrees F. to keep the RO membranes from puckering and slowing down my productoin. That means that I have to use the water in my hot water tank and it's already softened, ie even if I turned on the bypass on the water softener it would take days for the hot water tank to flush out.

Thanks again!
Jeff