Using RO water for water changes

[Gbark]

Hi,

If you decide to use RO water for your water changes, should you add GH booster to raise the GH (to lets say 5 for arguments sake).

And also add the recommended GH amount for your tank size as laid out in the EI thread?

 

[Tom Barr]

Most folks blend RO to get a desired KH, the GH is generally high enough still, and higher than the KH in most cases.
So if you knock the KH down to 3, from say 10, your GH is likely 10 or higher as well, so you end up with 3GH etc also.

Some folks go 100% RO, not sure why, not good reason unless there's really high copper or something really bad.
Some like to suggest so they 100% sure of the make up water.
Well, I guess, more work, wasted water, add the stuff back you just took out, no need to drop the KH below 3 really etc

Regards,
Tom Barr