Originally Posted by AyalaCookiejar
I really don't understand higher pHs much. I should have paid more attention in science. I do know that an acidic pH like 4 doesn't really sound like a lot of fun. I'm sure a few plants and fish could adapt but not many. It's considered an "extreme" environment, kind of like Antarctica :p
The pH scale is similar to the Richter scale used for earthquakes.
It runs from 0-14, where 7 is 'neutral'
--> 0 to 7 is the acidic side.
--> 7-14 is the basic (alkaline) side.
Each number is a ten-fold increase or decrease in acidity. As the numbers get LOWER, the solution is MORE acidic.
So say you have three solutions:
A) pH = 8
B) pH = 7 (neutral)
C) pH = 6
Solution B (pH=7) is 10 times more acidic than solution A (pH=8).
And Solution C (pH=6) is 10 times more acidic than solution B (pH=7). (This also means that solution C is 10x10 times, or 100 times, more acidic than solution A!)
- Pure water (H2O) has a neutral pH (7).
- Household vinegar has a pH of 2.8 (acidic).
- Seawater has an average pH of 7.5 to 8.4 (slightly basic).
- Some bacteria (like Vibrio) can survive a pH of over 10 (very basic/alkaline)!
SOME salts will change the pH of a solution. Others will not. (The explanation for this is chemistry-related, and is based on whether the salt is derived from a strong/weak acid or base.)
So pH is just a measure of how acidic or basic (alkaline) a solution is....
But water hardness and softness is very different from this.....
"Hard water" contains a lot of dissolved minerals (salts), such as calcium and magnesium ions.
"Soft water" has very FEW of these dissolved minerals (salts).
The 'hardness' MAY affect the pH. But it may not -- it depends on what salts are dissolved in the water. For example, adding pure sodium chloride (NaCl) will NOT affect the pH.... But adding SEA salt will raise pH slightly (making it more basic), because it contains different salts that do affect pH.
Clear as mud?