I think I might have so kind of infection in my tank. I bought 5 NTT datnoids the other day from the LFS. I did not quarantine them. It has been 4 days since I had them in the tank. Yesterday I noticed one of the NTT has some kind of infection near the gills - red color and looks kind of inflamed, it's not in the gill but outside of it on the gill plate. I was looking at my Arowana and noticed that it is twitching, fins twitch, mouth, barbels twitches. I think the NTT's have some kind of infection. Anybody might know what this is and the right treatment? The Aro is about 17" and the NTT are about 2-3". The tank is 168g filled about 80%. I also noticed the Aro is staying at the bottom of the tank sometimes, this is the first time I've seen it do that. Any help is appreciated it.