pH as a "meh" indicator for Alk. Dosing kalk based on pH?

chaostactics · Nov 11, 2021

So I have this idea of using two ATO pumps in my reservoir and having them be controlled by the Apex based on tank pH.

More specifically 1. ATO is triggered by low water sensor. 2a. If pH of the tank is above x (I dunno 7.9) then the pump that goes directly from the reservoir to the sump kicks on. 2b. If the pH of the tank is equal to or less than 7.9 then the ATO will route water into the Kalk reactor.

I know pH is certainly not a great dictator of alk but in general would this scenario be better than nothing?

arking_mark · Nov 11, 2021

Tank evaporation will be roughly 1.25% of total volume.

That amount of saturated Kalk would raise your alkalinity by about 1.4.

pH impact of kalkwasser is temporary.

Using ATO to dose Kalkwasser will cause pH spikes. This is why most people drip kalkwasser.

Depending on your set point, you're most likely to be always dosing Kalkwasser.

So it your tank isn't consuming Alk at the rate being added, you will have rising Alk.

vtecintegra · Nov 11, 2021

Highly discouraged unless you are using something like a Trident to constantly monitor alk.

chaostactics · Nov 11, 2021

arking_mark said:
Tank evaporation will be roughly 1.25% of total volume.

That amount of saturated Kalk would raise your alkalinity by about 1.4.

pH impact of kalkwasser is temporary.

Using ATO to dose Kalkwasser will cause pH spikes. This is why most people drip kalkwasser.

Depending on your set point, you're most likely to be always dosing Kalkwasser.

So it your tank isn't consuming Alk at the rate being added, you will have rising Alk.

Ive found it to be common practice to add kalk directly to ATO water and or always run ATO water though a kalk reactor before going into the sump.

Figured my approach would lead to a safer version of that?