Filter on 'not' on Alerts tab

We would find it useful to be able to omit certain datasources from alert tabs. In our use case, we use a Volume Usage warning at 80% in order to generate a report that our customer requested. However it is safe for us to ignore those warnings when looking at the alerts for that customer, as there are lots of them and they tend to obfuscate the real alerts. Being able to have a datasource filter of "!Volume Usage-" (NOT Volume Usage) would be a great help. This NOT filter might also be useful in other data columns.