A better workflow is to have Aperture use your existing iPhoto library rather than maintaining separate libraries for the same photos. That avoids unnecessary duplication and saves disk space.

Based on the advice given, you could even simplify further: stop using iPhoto as the main import tool and import photos directly with macOS Image Capture, then manage and edit them in Aperture.

So the practical recommendation is:

• Don’t use iPhoto as a “catch-all” if Aperture will be your main organizer/editor.
• Point Aperture at the existing iPhoto library if you want to keep your current photos without duplicating them.
• Consider importing future photos directly instead of routing everything through iPhoto first.

That keeps your workflow simpler and avoids wasting storage on multiple copies of the same images.