How to lower PH without RO and tannins?

  • We are currently upgrading MFK. thanks! -neo
Kind of... pH does definitely have an effect on fish well being on its own. Try keeping fish in pH 2 water! or pH 12. Dissolved CO2 reduces pH by the formation of carbonic acid which is a proton donor (weak acid, puts H+ into the water) and pH is a measure of H+. The "p" in pH is an operation that means "take the negative log" of H which the concentration of H+ (not H-) ion in molar units. pH levels and mineral content are not entirely separable. The dissolution of different metals in water changes pH. If you drastically change pH you will precipitate out some metal species and others will come into solution.

Anyways to OP- why are you opposed to using RO water?

The Ph itself does not tell you the amount of hydrogen ions in the water. So at s ph of 2 one tank might
 
The Ph itself does not tell you the amount of hydrogen ions in the water. So at s ph of 2 one tank might

What? Thats exactly what pH is. A measure of hydrogen ions....
https://en.wikipedia.org/wiki/PH

Sorry, something happened to the first post and the lot of it is missing.

To finish the above sentence, PH is not just a logarithmic value, its a ratio., measuring the ratio of hydrogen ions, not their number. It measures ratio of proton donors(acids) to one proton acceptor(base). So knowing the Ph, is knowing the ratio but not the actual numbers. Water with the same value Ph in one tank could be way more acidic than another tank with same Ph. So yes, all water stats are related but the actual Ph value is not the issue, especially in softer water where it is totally meaningless.
 
To elaborate further on the above, take for exampe a Ph of 2. It tells you that there are 100 proton donors for 1 proton acceptor. You can have 100X10,000 proton donors for every 10,000 aceptors and you can have 100X10 proton donors for every 10 proton acceptors but the ratio.i.e. Ph will stay the same value of 2, meaning that knowing the Ph doesn't mean you know anything about your water quality and tanks with exactly the same ph can have vastly different water quality.
 
To elaborate further on the above, take for exampe a Ph of 2. It tells you that there are 100 proton donors for 1 proton acceptor. You can have 100X10,000 proton donors for every 10,000 aceptors and you can have 100X10 proton donors for every 10 proton acceptors but the ratio.i.e. Ph will stay the same value of 2, meaning that knowing the Ph doesn't mean you know anything about your water quality and tanks with exactly the same ph can have vastly different water quality.
Wow, thanks for the info!
 
Wow, thanks for the info!
To elaborate further on the above, take for exampe a Ph of 2. It tells you that there are 100 proton donors for 1 proton acceptor. You can have 100X10,000 proton donors for every 10,000 aceptors and you can have 100X10 proton donors for every 10 proton acceptors but the ratio.i.e. Ph will stay the same value of 2, meaning that knowing the Ph doesn't mean you know anything about your water quality and tanks with exactly the same ph can have vastly different water quality.

No this is incorrect. pH is a measure of H+ ion only. By definition. Just look at the wikipedia page for pH. Or virtually any other source. You may be thinking of the Henderson haseelbach equation which measures the ratio of base to acid to determine the buffering characteristic of a solution. This does not negate the sorenson definition from which the henderson hasselbach equation is derived. It is poor to use this equation to describe the pH of an aquarium because the Henderson Hasselbach equation is defined for the dissocation of one species only!! And in a biological system there any many more species of interest. Besides, you are leaving out a fundamental part of this equation which the pKa of the species in question. Also it is typset pH, not Ph or PH or Ph because a lowercase p indicates negative logarithm (same with pKa, pKb etc)

I am a PhD student in analytical chemistry.....
 
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No this is incorrect. pH is a measure of H+ ion only. By definition. Just look at the wikipedia page for pH. Or virtually any other source. You may be thinking of the Henderson haseelbach equation which measures the ratio of base to acid to determine the buffering characteristic of a solution. This does not negate the sorenson definition from which the henderson hasselbach equation is derived. It is poor to use this equation to describe the pH of an aquarium because the Henderson Hasselbach equation is defined for the dissocation of one species only!! And in a biological system there any many more species of interest. Besides, you are leaving out a fundamental part of this equation which the pKa of the species in question. Also it is typset pH, not Ph or PH or Ph because a lowercase p indicates negative logarithm (same with pKa, pKb etc)

I am a PhD student in analytical chemistry.....

So taken from your reference Wikipedia page:

"It is approximately the negative of the base 10 logarithm of the molar concentration, measured in units of moles per liter, of hydrogen ions.

Molar concentration (also called molarity, amount concentration or substance concentration) is a measure of the concentration of a solute in a solution, or of any chemical species, in terms of amount of substance per unit volume. A commonly used unit for molar concentration in chemistry is the molar which is defined as the number of moles per litre."

So could you please translate that in mathematical terms?
 
So taken from your reference Wikipedia page:

"It is approximately the negative of the base 10 logarithm of the molar concentration, measured in units of moles per liter, of hydrogen ions.

Molar concentration (also called molarity, amount concentration or substance concentration) is a measure of the concentration of a solute in a solution, or of any chemical species, in terms of amount of substance per unit volume. A commonly used unit for molar concentration in chemistry is the molar which is defined as the number of moles per litre."

So could you please translate that in mathematical terms?

pH = negative of the base 10 logarithm of the molar concentration

pH = -log[H+]

molar concentration = moles solute / liter solute

1 mol = 6.022 x 10^23 of something

molar concentration : how many moles of the thing in question (in this case H+) in one liter

so pH is a measure of how many moles of H+ are in a given amount of solvent (e.g water). The reason we use the negative logarithm is simply to make the numbers easier to deal with. Because its a negative logarithm, more H+ is a lower pH (eg 4), less H+ is a higher pH (e.g. 10).

The pH of pure water is about 7 because this is the amount of H+ that water produces by autoionization.

:)
 
My RO system both broke because my PH was too high and I didn't want to replace filters after a week. I want to keep German rams and SA Plecos, but my water is too hard.

In the end you want, soft and acidic water. In order to truly soften the water you need to reduce the total dissolved value (TDS) level using dilution, which in turn should lower the PH. Mixing RO water or distilled water with your tap water will soften it by reducing the amount of calcium and magnesium; reducing the TDS. The PH will become lower as result.
 
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To me, keeping Rams, and soft water cats in your high mineral content, high pH water would be like beating your head against a wall to stop a headache.
One of my favorite fish is Uaru fernandezyeppizi, but keeping them in my high pH Milwaukee tap water would have been an exercise in futility, and the health of that species would be in constant jeopardy, so I didn't/wouldn't keep them living there.
If you have a local breeder in your area, that uses tap, you may be able to get by, but if it were me, I'd find something mose fitting, Or... be prepared to have your RO machine workin 24/7, start a tannin water reactor ( because soft water is not the only factor in their health) , and collect all available rain water, and get many barrels to store it in.
Luckily they are a small species, so you won't need thousands of gallons per month like I would for the Uaru I wanted.
 
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