Don't use chemical pH alterers! I can not stress that enough! If you use a chemical mean to change your pH, your pH is going to end up very unstable, and that will stress your fish far more than a stable pH that is a little out of their range. A pH of 7.2 is nowhere near far enough out of range to do any real damage. In fact, I hunted around the internet a bit and a lot of sites I checked said that the pH range for angels is 6.0-7.2, so you are completely in range for them, and that kribs like 7.0, which means a pH of 6.5 would be farther from what they like than 7.2.
The only real negative side effect of a slightly high pH will be that the fish are going to be a little less likely to reproduce, but unless you are actively seeking this, it shouldn't be too big of a deal. One thing to keep in mind is that the average range for stream water pH is about 5.5 to 7.5, and a lot of freshwater tropical fish will have lived in streams in the wild, and you fall well within this average.
If you are still concerned over your fish and want to lower the pH a little, you do have some options left for doing so that don't resort to chemicals. Injecting
CO2 (or more
CO2 if you are already doing so) will help to lower your pH, as will adding peat moss to your filter or to the water you add to your tank (done by aerating water in a bucket with peat moss in it for a few days before a
PWC).
Here is a good website that addresses all this:
http://faq.thekrib.com/begin-chem.html
I hope that helped!