You could add something a lot less potent to the water than bleach, such as baking soda to raise the pH a bit. And a good way to test the pH would be to buy some litmus paper and cut the strips yourself. Or as dll said you could control the pH using a kit to maintain the pH of aquariums.
To lower the acidity(pH) you will need to add a solution containing H+ (or more specifically H3O+) ions, like chloric acid (Cl- H+).
If you dilute it it is also ok
If you dilute it it is also ok
The easiest way is to dilute your water with distilled water which has a neutral pH... And I know food grade citric acid is sometimes used in organic gardening to lower pH... So I assume you could lower it by simply adding a little lemon or lime juice, but I don't know how you would determine how much to use unless you have a pH testing kit, in which case you could figure it out by trial and error. Also, any store that sells aquarium fish or fish supplies will sell pH adjusters that are diluted in accordance with the amount of water being used.