I'm thinking about buying an Angelfish I saw in a local fish store. The tank it's kept in is on a R O system and has a PH of 5.5. My tank at home has a PH of 6.8. No R O system. I Just change my water 50% 2 times a week. Have a FluvalFX5 and 2 Aquaclear 110 filtering it. I know how to acclimate. I usually take about an hour to acclimate new fish. Do you think there will be any problem. Btw it's a 90 gallon tank with 10 Angels and a couple of bristle nose Plecos.