So I got what I think was velvet or brooks was never 100% sure. I fallowed the tank for 8 weeks before adding back 1 surviving clown fish and 1 I had paired with it in quarantine for about 4 weeks. 24 hours of them being added to the infected DT the survivor died in 24 hours and the new one died after 72 hours. I have now gone and fallowed again for 90 days. I have added 4 chromis and wondering how long I should leave it before we can deam the tank cured. They have currently been in for 24 hours but I no they are hardy fish