The ph coming out of the faucet in the sink is 7.8 I don’t consider 7.8 to be almost neutral. I also don’t think it’s acceptable that the ph in the tank is below 6.0. I don’t want to decrease the ph in the tank I want to raise it. I just don’t know the best way of doing it without shocking the fish. I can do gradual water changes but eventfully then I’ll have it up past neutral. I really don’t think the tetras like it that high, do they? Yes there are a few tetras in there I had neglected to mention. Do you recommend powder or drops to neutralize it? Which work better? What are the dangers of stressing the fish?