Not as drastically. I'd be concerned about other swings like temp to affect the fish before the nitrates would. If it were corals I'd be more concerned as they are much more sensitive to spikes and swings in parameters. Even a drastic drop in 'bad' parameters can be stressful, which is why the instructions on GFO
says to start adding slowly and more over time.
This said, I wouldn't want to do anything larger than a 50% in a day just so nothing was shocked from any drastic swing. I might be on the more sensitive side of things, but I don't want anything to stress out my corals.