How much is too much?

No, TDS is non specific, a lot of K+ can contribute, but not harm plants, whereas Na+ would even if the TDS were the same.

Regards,
Tom Barr

 

TDS is non descriptive truthfully, it does not tell you what the dissolved solids might be.

Some plants appears sensitive to KH, but not to TDS, unless the TDS is due to KH.......

See?

It's better/best to be as specific as you can and give specific details, such as a 20ppm to 100ppm of NO3, rather than these bozos that say high NO3 is bad.

What the heck does high NO3 mean?
5ppm?
50ppm?
500ppm?

 

The Ichetucknee river had a pH of 6.7 and a KH of 6, about 25ppm, that was in the middle of the afternoon so some plant uptake should be factored in.

Plenty of ground water is loaded with CO2.
That's how caves are formed.
The acidic CO2 rich water dissolves the limestone.
As rain falls and percolates through the soil, the organic matter is decomposed in the soil, this uses up O2 and gives off CO2 by the bacteria in the soil.

The CO2 is absorbed into the rain water and descends into the water table below.
There is nowhere for the CO2 rich water to off gas underground, so it builds up.
Where there are springs, the water coming out is typically loaded with CO2 and plant growth is vigorous and stable for well over hundreds of years(500 years at least in Florida based on observations from Spanish monks in 1500's, even longer based on radio labeling and pollen and other indicators of dating in Paleolimnology).


In answer to the 2# question, the answer is a resounding "no".
CO2 is also an acid, ask yourself why that does not work also?
Because the acids you listed are "weak" acids.

If you used a "strong" acid, then the answer is yes.
H2SO4, HCL, HNO3, etc, nasty stuff, this will attack the bicarbonate and release CO2.

It'll also soften the KH
It's virtually always a much wiser idea to use RO if you want less KH than strong acids. I've had folks carry on about having it for their pool etc and how easy they claim it is on line..........but I've done it also, it's not this easy thing, the flumes are noxious and the acid is nasty stuff and many burn the heck out of themselves.
I asked this same person that claimed to know what they where doing whether or not you should add acid to water or water to acid to diluted.

They gave the wrong answer.
That told me either they are not really doing it and just wanting to make a stink and haggle, a common thing on the web really, or that they forget even though they claim to have been doing it.

I use long gloves, a fume hood, apron etc.


Look, bottom line, if you want more CO2 in the water, it is very simple: add more CO2 gas. Plants want CO2, so provide that.

Changing pH/KH etc does not add CO2.
Adding CO2 adds CO2.

It's much simpler than you are trying to over think it, don't fret, many folks do and go through this same thought process. But then they realize the simple aspect, if you want more CO2, add more CO2, it's much simpler than any other method.

Regards,
Tom Barr