With densely planted tanks, you don't vacuum the substrate as that can damage roots systems. As I start a water change, I wave my hand over and through groups of plants to loosen up any debris - uneaten food, loose pieces of leaves, decaying leaves, etc. - and then you can get those with the vac or let the filter tank smaller debris out.
And I don't do as large a water change as Convict is talking about - only on my goldfish tank. IMO if you need to do a 50-75% water change to get ferts out, you overdosed. Otherwise at proper doses, the plants used the ferts.