I think you might be confusing salinity with pH. If you want to work with the African Rift Lake Cichlids you want to have a higher pH; 8.5. You can sometimes attain that by using a buffer such as crushed coral, but it is going to depend on what your water is out of the tap or your water source.
Salt as a salinity is a debatable issue, while some people use salt on a regular basis, others disagree and don't see the need for salt at all. Some people like to use salt for a first prevantive against disease; such as parasites or bacterial, but it is really a personal prefernce. Many people think that salt irritates your fish.
The other issue is that some people confuse salt (salinity) with Cichlid Salts, or rift lake salts, which are not really salt, but a buffer that adds minerals to the water, and this would also increase your pH.
I know that sometimes this can be really confusing, it is compounded with the issue that everyones water is different. So you need to test your water direct from the tap, and measure your pH, you may not have to add anything. If your pH is lower then what you think it should be then test it again out of your tank with the crushed coral, to see how much the coral has raised it.
Personally I only worry about the pH, not the hardness or the salinity. Generally speaking if your pH is high, the hardness will follow behind it, and so it isn't an issue. Then remember that salt as a salinity is not going to raise your pH, it is only going to make your water salty.
Hope that helps!