When to test? Does it matter?

[AdamK1]

So I test my tank quite a lot at the moment, but now things are settling I'm going to move to weekly. Really just testing for nitrates, phosphates, and alk, and adjusting dosing of nopox and triton core7 flex other methods 2 part accordingly. I also do weekly 10% water changes.

When in relation to water changes would be best to test? Presumably just before or after will likely give extremes, apart from alk, which I match my water change water to. But does it really matter?

 

[Biokabe]

It doesn't matter, so long as you always test at the same time to maintain a consistent testing environment. Day-of water change, immediately after water change, three days after, two days before - doesn't matter so long as you are always testing at the same time relative to the change.

Ideally you should do a sample test for a few complete water change cycles (testing every day) so you can see how your parameters are changing as time goes by. After that, just pick a day in the cycle to do your tests and compare it against your baseline so you can see if anything is majorly out of whack.

 

[CBonito]

Test once at the peak of the photoperiod and once in the middle of lights out for a few days. That will tell you a lot of things.

 

[Reefer911]

Not an expert, but I’d say just before a WC. In my mind, you want to know how to what degree your parameters are rising or falling. If you’re religious in those weekly water changes and only test right after a WC, you don’t know how high your PO4 gets, for instance. You can always subtract 10% after a WC to estimate the difference.

 

[AdamK1]

Test once at the peak of the photoperiod and once in the middle of lights out for a few days. That will tell you a lot of things.

Hmm, interesting. How quickly does water parameters deteriorate? I'm not getting up at 4am to draw water, but I could set a dosing pump to pull some out and test the next day.

 

[gbroadbridge]

So I test my tank quite a lot at the moment, but now things are settling I'm going to move to weekly. Really just testing for nitrates, phosphates, and alk, and adjusting dosing of nopox and triton core7 flex other methods 2 part accordingly. I also do weekly 10% water changes.

When in relation to water changes would be best to test? Presumably just before or after will likely give extremes, apart from alk, which I match my water change water to. But does it really matter?

Testing consistently is all that matters.

You could do it before a water change, after, or halfway in between. It doesn't matter.

What you're measuring is a trend going up or down and as long as you perform the test at the same time (say 10am) you will be able to plot any changes week to week.