pH & Hardness
I find it interesting your nitrates test at 0. You must be a water change fanatic too. Anyway, your pH is fine. 8.2 is on the alkaline side, but most tropical fish prefer this type of water.
You don't need to worry about pH, hardness, etc. If you treat your tap water for the standard things like chlorine, chloramine and ammonia, then your fish and plants will adapt.
I would recommend getting some plants into your tank. Your fish will feel more comfortable if they have places they can hide.
"Fear not my child, just change the tank water."