My water supply has low KH

[richarddeweerd]

let's explore that in detail.

Suppose that you have fresh water with an alkalinity of 1.0 dKH (0.36 meq/L).

It must have either

0.36 mM hydroxide (OH-)
or
0.36 mM bicarbonate (HCO3-)
or
0.18 mM carbonate (CO3--; carbonate carries two units of alkalinity)

There must also be counterions present since one can never have just negative charges in water.

Let's assume it is sodium, which is most likely, but the assumption doesn't matter much. In each case, we will have a total of 0.36 mM sodium to balance charge.

How conductive are each of these solutions? We can look them up.

0.36 mM (14.4 mg/L or 14.4 ppm) sodium hydroxide has a conductivity of about 31 ppm TDS
0.36 mM (~30 mg/L or 30 ppm) sodium bicarbonate has a conductivity of about 20 ppm TDS
0.18 mM (19.1 mg/L or 19.1 ppm) sodium carbonate has a conductivity of about 20 ppm TDS

Thus, if the RO/DI water has a TDS of 0-1 ppm, it really cannot have anything close to 1 dKH of alkalinity. Maybe 0.05 dKH max for 1 ppm TDS.

If I knew in high school that chemistry would be important later in my life for the health of my animals I would have paid more attention during the lessons.

 

[Miller535]

If I knew in high school that chemistry would be important later in my life for the health of my animals I would have paid more attention during the lessons.

For sure!

 

[Randy Holmes-Farley Verified Community Expert]

If I knew in high school that chemistry would be important later in my life for the health of my animals I would have paid more attention during the lessons.

lol

Happy Reefing.

 

[richarddeweerd]

lol

Happy Reefing.

But on a serious note, thanks for all your input.

People in this hobby do a lot of things just because they think it is right, or because "everybody is doing it like this for years". It is good to see some scientific analysis in this field.