I am pretty new saltwater aquariums. I have had some freshwater tanks in the past but I have just recently decided to set up a saltwater tank. I currently have 2 clownfish in a 20 gal QT tank. I have been checking for ammonia daily, and levels have not risen over 0.25. I have been doing 50% water changes as need to keep ammonia low. They have been in QT for exactly 2 weeks now, and when I went to look at them today I noticed one of them had a noticeable red mark on its head that was not there previously. The other clownfish in the tank is a little larger than this one. I have seen the larger one nip at the smaller, but never right on top of its head, and there are no other red marks that I can see. My first thought after looking through some threads is that it is a bacterial issue, so I was planning on using some kanaplex to rule that out. I have also seen that red marks can randomly appear on clownfish and no ones really sure why. I would just be interested to hear what others think and I would definitely accept any advice. I have included a link to a video I took and some pictures of what he looks like now, and the second picture is what he looked like 2 weeks ago when I first put him in the QT tank.Thanks in advance.


