It is a convention.
A pH of seven is called neutral. E.g Water
a pH of seven is said to be neutral (without acid)
It differs from aquarium to aquarium but it is generally just about seven and can go to about eight. It should never be below seven because that is too acidic for fish. Different fish prefer different pH. Some fish will like it around seven, others around eight and some in the middle of the two.
For example a pH=4-5.
Pure water has a pH of 7.0 which is the center of the pH scale.
Sure, here are a few words with "pH" in the middle: morph, trophy, phosphate.
solutions with a pH less than seven are acids. solutions with a pH greater than seven are basic. if a solution has a pH exactly equal to seven it is neutral. there are many more also i just gave you 3 of the answers.
No, pH ranges from 0-10 anything below seven is acidic (closer to zero is more acidic) and anything above seven is a base.
"Neutral".
Seven
Seven
A pH of around seven (7) is ideal.