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fatrip
06/04/2007, 08:31 AM
hey guys i was thinking about the rock we made and how tonight i am goin to put one of my toilet pieces in a bucket to test the ph. i am just curious if any one knows the PH of RO/DI water...i know theoreticly if there is only H2O it should be 7 but i find that hard to believe that it will be... thanks

jacksonpt
06/04/2007, 08:52 AM
This may be a stupid question, but does salt affect PH? FWIW... my freshly mixed saltwater (used for water changes and topoffs) tests at 8.2.

fatrip
06/04/2007, 08:54 AM
yes the salt we use has many other nutirents in it that affect the ph.

Piazzon12
06/04/2007, 09:35 AM
you could always just test it

fatrip
06/04/2007, 09:36 AM
i know but i am at work right now and i was wondeirng if any one new off hand...lol...

RyanM
06/05/2007, 12:36 PM
I know this is a day late but some may still find it helpfull.

1. The pH of totally pure water is around 7 (with the exact value depending on temperature). As carbon dioxide from the atmosphere enters the water, the pH drops into the 6’s and even into the 5’s, depending on the amount of CO2. At saturation with the level of CO2 in normal (outside) air, the pH would be about 5.66. Indoor air often has even more CO2, and the pH can drop a bit lower, into the 5’s. Consequently, the pH of highly purified water coming from an RO/DI unit is expected to be in the pH 5-7 range.

This came from a reef keeping artical and here is the link.

http://www.reefkeeping.com/issues/2005-05/rhf/index.php

Piazzon12
06/05/2007, 03:13 PM
Thanks Ryan, I thought it was lower than 7, but didn't know why, hence my useless post earlier