Best way to kill yellow stone polyps

[Privateye]

I'm looking for the best way to kill yellow stone polyps once and for all. bought some years ago and it's easy to get rid of most of them, but they are almost as invasive as aiptasia. Are there any biological controls that won't harm other corals? Every few months I scrape a few square feet of them off the back glass, but some always remain somewhere. Here's a pic with the back wall covered. I don't want my nutrients going to them any longer.

 

[blaxsun]

More frequent scraping? Your tank looks great!

 

[Aspect]

Scrape them off and send them to me