Time for Alk/,Ca/Mg to Disburse?

[Tony the Fish]

How long after dosing either alkalinity, calcium or magnesium is it safe to retest my aquarium water. Is 1 hour sufficient in a tank with good flow?

 

[KrisReef]

Yes, you can probably "safely" retest immediatly. If you have a sump and a tank I would wait until the return pump had time to completely turn over 2x the total volumn of water in the system if what you are trying to assertain is the resultant change in those parameters after the add? The other thing that impacts your results will be uptake by animals and abiotic receptors of ions. When you are first setting up a doser if makes sense to test daily (about the same time each day) to track the impact(s) of chemical additions, and continue long enough until you are confident that you have control and stability in your target range. hth?

Merry Christmas @Tony the Fish ! Your fish will love you if you does mysids!