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My fantail goldfish might have fungus

23 11:12:23

Question
the sick fantail
the sick fantail  
QUESTION: Hello Jaymie,

   Thank you so much for your time! One of my calico fantails seems to have the beginnings of fungus. It seems to have velvety growth on a large area on one side. The growth is gray and seems fuzzy, but it's hard to discern unless you really look for it and see it at the correct angle of the light, so I'm not sure if it's fungus. I only noticed it when I examined the fish carefully because it shows obvious discomfort (spending lots of the time hiding with fins clamped). I also noticed a small red streak on its tail fin, probably with the same root cause- stress. I used to have two platies that were bullying this fantail in particular so i returned them, they used to constantly pick at the fantail's fins and side. Fish still eats normally and perks up like normal when I approach the tank and talk to it.
  Tank info: Tank has a whisper filter for 30-60 gallons, I use tap water treated with dechlorinator. I change 25-30% of the water every week/two weeks, this past week I have changed 10% of the water for several days, in an effort to help the fantail. I do not have a test kit, so do not know the parameters, but mostly the fish tend to look content and active. I have several live plants in the tank, which is usually at 74-76 degrees F.
   The sick fantail is 4 inches including its tail, I also have another fantail the same size (they're always together, I've had them both for about 4 months), a smaller comet (2 inches, I've had about 3 months) who gets along with them well, a one-inch comet that was recently added, two neon tetras, one zebra danio, and a 3-inch pleco I recently bought. (I have since read that plecos will suck on fantails... do I need to return him? If I keep him properly fed with algae wafers will he not disturb the goldfish?)
 I had some fungus eliminator tablets by Jungle products and added a partial dose to the whole tank, since I read that it should be safe for all fish, including plecos and tetras.. But I've been afraid to use the full dose. A normal dose of ich medication (Wardley malachite green) I used a while back led to all my goldfish dying overnight; I also used Aquari-Sol for ich and some of the fish, seemingly healthy one day, were dead the next. So I'm always hesitant to use medications, or the full dose. Please advise as to how to proceed.. and any advice on anything I'm doing wrong. I really want my fish to be healthy!

ANSWER: Darliz,

 Sorry to hear you are having problems. Goldfish do tend to change their colors but I don't think that is whats going on with yours. The red streak in the tail is concerning since that is usually a sign of ammonia/nitrite poisoning. It is very important, if you are going to keep fish, to get a water tester. Goldfish are very delicate and do not do well if the water perimeters are off. As you may know, they do not have a stomach and the food comes out as ammonia. One of the top rules of fish is to never treat them with any medication unless you are 100% sure what disease they have. The first thing I would do is remove the sick fish and put him in your hospital tank. That way you are only treating him not the whole tank population. I think it would be in your best interest to purchase a water testing kit if you want to continue to have fish. The water needs to be tested weekly along with weekly 25% water changes. Now you have a problem other than sick fish. You have tropical fish with cold water fish and that is not good. Your fantail is a cold water fish and everyone else needs warm water. That there can be the real reason the fish is sick. You need to figure out what type of tank you want and fill it with the appropriate tank mates. To make sure your goldfish gets healthy and stays healthy he needs to be removed and placed in a cold water tank. Faintails do much better in very cold water. They are the most sought after goldfish for the outdoor ponds. I think once he is put in the right environment, as soon as possible, he will do much better. I think he is stressed and that is why the change of the color on the tail area. If he is eating well and swimming well I would not treat him with any medication at this time since you have in the past and it isn't working. Once you remove him and he doesn't get better, or he gets worse, let me know.

---------- FOLLOW-UP ----------

QUESTION: Thank you very much Jaymie :) I'm sorry I'm only now replying, the email got sent to my spam folder... sorry... My fish seems to be doing a whole lot better, she looks back to normal, thank you. The red streak went away and she's all perky like usual. Water test results came back good as well. I do have another question, though.. You mentioned that my tropical fish need warm water.. How warm do they need it? I had read that goldfish can do well in water in the 60's to low 70's... and that tropical fish do well ideally in 70's.. so I had figured a water temp of 72 was good for both kinds. How cold does my goldfish water need to be, and how warm does my tropical fish water need to be? Thank you so much for helping :)

Answer
Darliz,

   I am glad to hear your fantail is doing better. As for your new question, your tropical fish like to be in water between 80 and 82 degrees. The fantail needs to be in much colder water. It would be in the best interest for your fantail to move him to a new tank with no heater. Fantails are very popular in the pond scene since the winters get cold and they can tolerate it.