Ok so this is strange. I know arowanas prefer PH at about 7 ish so i tested my water to see how the water conditions are. Its pretty high at 8.5 so I was thinking maybe my tapwater is just high so checked my tap water and it came out to 7-7.5? How is this possible? I did a 50% water change and same thing? I also have driftwood in my tank which is suppose to lower PH? Please any advice or help to lower my tank ph?