How Long To Keep

[jsker]

I have been looking around and cannot find the answer to my question of, how long can I keep my tank water sample for testing at home before the sample is not longer useful to test.


I see where water samples can be sent away for testing. I like to pull my sample just before I dose or just before I change my water so that I can make adjustments.

What are your thoughts?

 

[Randy Holmes-Farley Verified Community Expert]

Depends entirely on what you are testing. Salinity and some elements (e.g., sodium and sulfate) are forever in the water.

Some can undergo transformations that may change the measurements fairly rapidly (too rapidly to send away: pH, ORP).

Some may transform slowly and may or may not change during a week (e.g., some trace elements). There is very poor data on how these change in a sealed container.

 

[jsker]

Depends entirely on what you are testing. Salinity and some elements (e.g., sodium and sulfate) are forever in the water.

Some can undergo transformations that may change the measurements fairly rapidly (too rapidly to send away: pH, ORP).

Some may transform slowly and may or may not change during a week (e.g., some trace elements). There is very poor data on how these change in a sealed container.

Thank you Randy for the quick reply

Yes that is what I was noticing that there is very little information on how long a sample for the tank. There is a lot of information on how long freshly mixed salt can be held.
Ca
Mg
Alk
Phosphates
Nitrates

 

[jsker]

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