How to test tap water properly

[NadiaG]

I just realized I've never tested my tap water... I know, rookie mistake...

I heard I have to wait 24 hours to test it, is it true? For all categories or some of them can be tested right then and there? I have an API liquid test kit

 

[GreenLily]

I've always just tested straight away from the tap- have for years. I hope it's the right way, because if not, then I've been doing it wrong!

 

[flitabout]

No the water needs to be aerated or stirred frequently for 24-48 hours. This helps it to off gas so that you get accurate readings for a tap test.

 

[NadiaG]

I keep on hearing people do it both ways. It does make sense though, if you leave it out for a bit for stuff like chlorine to evaporate...

 

[Rivercats]

You only need to leave water out 24 hours either aerating it or stirring it occasionally allowing it to gas off. Gassing off is letting gasses like CO2 in the tap water to dissipate out so you get a true ph reading from the tap. Sometimes depending on the gas levels in tap water ph can be the same as in your tank. It just depends.

For the other tests such as ammonia, nitrites, nitrates, phosphates, gh, and kh you can take the reading right away.