First of all, I hope your wife is doing okay. My thoughts and prayers are with you both.
As for micro bubble scrubbing, most people do it at night for the benefits that it has on PH. Some opponents argue that the micro bubbles could get trapped in the gills of fish; I'm not sure on that, but if it is true, night time is also better as many fish tuck into the rock at night.
If it helps your wife to do so for a little while during the day, then go for it though; you can always stop if you see any adverse effects, but I think it will be just fine.
As an alternative, maybe consider setting up a small freshwater tank. As long as its not a high tech planted aquarium, you can do lots of fun stuff with bubbles... full air stone across the back and maybe a bubble decoration that opens and closes too. I have a low tech planted aquarium and my wife likes it much more than my reef tanks. In fact, she had to quit her job a couple of years ago due to health issues and she said while laying on the couch, looking at the freshwater tank helped her recover. It's a good community here, so if you decided to go that route and need some help, let us know. I think I may have a spare air pump and I bet others have some things going unused in a basement or closet; maybe someone even has a tank. I'm sure the medical expenses must be high.