Hi, i'm pretty new to the saltwater hobby and set up a tank about a month and a half ago. I fully cycled it and tested my ammonia and nitrate and it is both at 0. Recently, i got a clownfish pair and they are both very inactive after a week and one clownfish started swimming sideways and died eventually. I also got a cleaner wrasse and after a day it was lying on the floor breathing very heavily and also passed. I'm planning to get a new clownfish to pair with the one still survining but I'm afraid it will suffer the same fate.