So I was super excited that my lfs was selling medium sized zoa colonies for a decent price but upon inspection before purchasing I noticed a fish in the same tank as the colony had marine ich. I showed the owner and they promptly removed all the fish in the tank to quarantine but I was still wondering if I purchased the colony would there be any dormant ich on the rock? How long would I have to quarantine the colony to ensure there would be nothing contaminating my display? Thanks!