Water Chemistry

[Levin Tilghman]

I know that my tapwater here is moderately hard, with a ph of around 7.5. Would it be best to add RO water to lower the Ph? Or should I attempt to lower it by adding chemicals or an aquarium product specifically suited for this?

 

[anewbie]

You should focus more on tds than ph and it depends on the species of fish as different fish have different requirements.

gh and kh are also useful numbers.

 

[Apistoguy52]

Kinda depends on what exactly your tap water looks like. Moderately hard isn’t very specific.

If breeding is the goal, I would probably advocate for a measure of RO to dilute the hardness, and a measure of muriatic acid to target the pH of your choosing.

In my experience, you can get away with hardness that is 10x, 20x higher than “nature” for some species as long as the pH is correct

 

[dw1305]

Hi all,

Or should I attempt to lower it by adding chemicals or an aquarium product specifically suited for this?

You can't really make harder water "soft" by adding things, but you can make soft water harder fairly easily. As the others have said you can only really interpret pH if you have some measure of carbonate hardness.

Assuming that your water is hard and salts rich? Then RO (or Rainwater) are ways of making it softer via dilution.

You can burn out the carbonate hardness with an acid (which converts the HCO3- to CO2), but you've added an anion (in the case muriatic acid (HCl), a chloride ion (Cl-)) as well as a proton (H+) and raised the conductivity ("ppm TDS").

You can also reduce pH with "pH buffers", but you have the same "added things" issue and they don't really help.

cheers Darrel