You do not need to lower your ph unless you have super high or super low levels. Angels will do just fine in your tank as long as you properly
acclimate new fish. The only time you should alter your ph is if you have wild caught fish, or for breeding purposes, and that's only for certain species. Adjusting your ph can be unsafe for your fish when it doesn't stay consistent, and it is a lot more work trying to get the ph to match what you have in the tank when doing water changes. I have 4 angels in the same ph you have and they have been just fine for over 2 years.
