Ok just bought 6 corydora melanistius all are eating and are in my QT with 1 harlequin rasbora and 1 golden long finned danio. I noticed after I had already added them to the tank from the pet store that one of the cories has a white spot on the tip of the left pectoral fin. I had done a good water change before adding the fish to the QT and the other fish that were transferred to my 36 gallon previously before these fish were added were healthy and had no issues for more than one month. I put the new fish in after the water change on Wednesday night. As far as the cory I was not sure what to do since I am not sure what this is on the fin it looks like a white fuzz ball very small could this be fungus? The only meds I have in the house are pimafix and aquarisol. Is pimafix ok to use the bottle says it's good for fungus and bacterial infections? The other fish are ok so far I really hate when this happens and especially when am not sure what am looking at. I really like these cories if I do add pimafix will the other fish be ok and how often do I have to do water changes during the med process? So disappointed my restocking process for my 36 gallon was going so well. Need good advise desperately I really want to get all these fish through QT and not blow over $20 in fish purchase down the drain. THANKS!
. As shown in this pic the white fuzzy spot on the pectoral fin is still there but now the entire fin looks red. This morning I found that my golden danio died I could not see any obvious disease on him but he did look a bit scrawny. I had just purchased these fish on Wed I have been watching them closely the rasbora is doing fine but am thinking that I have to start meds or am I am going to lose these fish. Only this one cory seems to be affected right now but if this is columnaris or something like it am gonna lose all of them and just water changes is not going to fix this problem. I am attaching a pic I know the body of the fish in the pic looks white is just how the pic came out it's the fin that is the problem. It's the cory on the bottom near the back corner of the tank. My water parameters are fine and ammonia is at 0. I am going to dose with pimafix that is the only thing I have in the house that looks like it will help. Hoping this is the right thing to do. Crossing my fingers. See pic below the fish are in QT.
