I am a firm believer in the once a week minimum for water changes, though sometimes in the winter, I was not able to do those due to frozen water hoses. The issue is the dilution, primarily of nitrates, as the filters should be processing the ammonia and nitrite. The only way to keep the nitrates down is through dilution.
For bead filters and some of the sponge type filters, the cleaning of the filter is a reversal of flow through the media and out to waste, so using the filter cleaning as a means of accomplishing a minimum 10% water change serves two purposes, and utilizes pond water as the cleaning media. As was mentioned, use of hose water, unless you are on a well, means subjecting the filter bacteria to doses of chlorine or chloramine, which are put in our drinking water supplies to control the growth of bacteria in our water. I don't know how much it takes to kill a filter, as PP does the same thing and I have allowed PP to flow through my bead filters and not noticed a setback of the bio bacteria.
Zone 7 A/B
Keep your words sweet. You never know when you may have to eat them.
Richard