Angels and Rams can coexist as far as water as long as it isint too hard it should be fine. pH is just a general guide to judge the hardness of water...If your pH is lower than 7.8 you should be fine as long as you are not trying to keep wilds. I recommend not playing with water parameters too much as they will change slightly over time between cleanings, feeding and such. The fish will be much happier and you will have less stress in the long. I forget what size tank you have, of course tank size will impact what you can keep especially with Cichlids.
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"There he goes - one of God's own prototypes -
a high powered mutant of some kind never even considered for mass production.
Too weird to live, and too rare to die".
Fear and Loathing in Las Vegas