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One Dumm Hikk · 06-05-2009, 07:13 PM

It could be the trashcan or it could simply be the air above it. Take a glass container and a straw. Fill the container with RO/DI water straight out of the unit. Do a TDS reading on it. Take the straw, insert it and blow through it for 10 seconds producing bubbles. Do another TDS reading. Some of the air that you blow into it will dissolve into the water and read on the TDS meter.

RO/DI water (and distilled water) is pure water and very unstable. It wants to be at equilibrium with the environment around it. Whether that environment be pure CO2, pure O2, pure nitrogen, or even a Phosphate containing plastic can. It will do its best to absorb/dissolve so that it can come to equilibrium. Thats why blowing in the container of water will alter its TDS reading so quickly. You can do the same TDS test with tap water and it won't be as drastic or as noticeable because of the percentage change in TDS.

In other words, what you are seeing is normal and it doesn't necessarily mean its coming from the container, some of it is coming from the air above the water in the container.

06-05-2009, 07:13 PM	#4 (permalink)
One Dumm Hikk Feather Duster Join Date: Apr 2009 Location: Phenix City Alabama Posts: 212 Karma: 1306	It could be the trashcan or it could simply be the air above it. Take a glass container and a straw. Fill the container with RO/DI water straight out of the unit. Do a TDS reading on it. Take the straw, insert it and blow through it for 10 seconds producing bubbles. Do another TDS reading. Some of the air that you blow into it will dissolve into the water and read on the TDS meter. RO/DI water (and distilled water) is pure water and very unstable. It wants to be at equilibrium with the environment around it. Whether that environment be pure CO2, pure O2, pure nitrogen, or even a Phosphate containing plastic can. It will do its best to absorb/dissolve so that it can come to equilibrium. Thats why blowing in the container of water will alter its TDS reading so quickly. You can do the same TDS test with tap water and it won't be as drastic or as noticeable because of the percentage change in TDS. In other words, what you are seeing is normal and it doesn't necessarily mean its coming from the container, some of it is coming from the air above the water in the container. _________ Randy Chance Favors The Prepared Mind. Two things are infinite: the universe and human stupidity; and I'm not sure about the universe. Albert Einstien. The only thing that comes fast in a reef tank is disaster.