Hey guys. I have had my Datnoide for almost 2 years and he is about 4 inches. He lives in a freshwater 55g (I attempted keeping him in brackish when I got him and his whole body was entirely black until I moved him to freshwater) with a few African Cichlids, Spotted Leaffish, 3 Cories and 2 Plecos. Two weeks ago I decided to add some Platies to add color and excitement since the Cichlids mainly stay in the rockwork and figured they would be large enough to not be eaten. I bought them from Petsmart (I know not good but I'm in college= little money, and in case they became snacks didn't want to pay a ton). Well bought 6 of them, put them in all was fine, then came home last weekend (my mom takes care of all my tanks while I am at college) and all the Platies were gone (more than likely thanks to the Dat) and I noticed that 1/2 of the Dats head was pitch black. Figured maybe it was mood or something as he is quite the character. Left for college then came back this weekend and now his entire head is black along with his left fin and his left fin is paralyzed. So I took him out and put him in a 20g quarentine tank and put 3/4 of a cup of salt in, in case it was some freshwater parasite that couldn't withstand salt. Granted it is not a lot of salt but again, this fish does not like brackish plus he is used to plain freshwater so couldn't take him up too quickly. He still eats readily so does anybody know what this is or how to fix it? I have never seen or heard of it and don't know where to begin to try and help him. I really don't want to loose him but am afraid I may as the amount of progression it made in a one week period. Anyway, any help you can guys can give is much appreciated. Thanks in advance!
