8.2 is just fine.
I just want to add that your PH will fluctuate. To get a good feel for your PH test it just as the lights come on and then again just after they shut off. Ideally it shouldn't vary but in the real world it shouldn't vary more than 0.2
Aquaman 8.2 is great and will iincourage a healthy aquarium.
Over time however most aquariums will eventually lower in ph due to lack of bicarbonates found in contained systems. Unlike the ocean which has unlimited bicarbonates keeping a stable ph. I add sodium bicarbonate (baking soda) in new water when performing water changes. Keeping ph in the 8.0 to 8.4 range for years.