my fantail goldfish has black blotches!

Question
Hello Chris R. I don't have a tank, I have a fishbowl. I know that I really should have a tank but my parents won't allow me to have a tank and we don't have room. I have 1 fantail goldfish. I did have a comet but it died, I believe from tailrot (I got the medicine but it died anyway much to my distress). I was away for a week (in which my mother was taking care of my goldfish) and then when I came back I found that my fantail goldfish had black blotches all over her body! Is this normal? I change the water 1-2 a week but I couldn't change it the week that I was away. It doesn't look like fungus or anything, but because my other goldfish died I'm worried about her! Could it be because I hadn't been able to change her water for a week or so, could she have fungus, or is it normal in fantail goldfish? Also, I believe that my goldfish is a female how do you tell the difference between male and female? Thanks.

Answer
Hi Rachel;

The black blotches are ammonia burns. They were definately caused by lack of water changes while you were gone. Ammonia comes from fish waste. The burns will heal but even if the fish does survive for awhile, that's all it's doing. It's just barely surviving. There is just no way you can keep a goldfish healthy in a bowl. I know you really have tried hard but it just can't happen. Each goldfish needs 10 gallons of water and good filtration. They are tremendously messy fish, get to be 6 to 8 inches long and keep growing no matter what size tank they are in. Even if you changed the water every day, it still will not survive for much longer in the setup you have now. Here is a web page about goldfish bowls;

http://www.fishpalace.org/BowlMyth.html

It would be best to take the fish back to the store if you can't get a regular fish tank of at least 5 gallons. A betta fish is a better choice and more suitable for a fish bowl. They stay small and don't need a filter. Here is a web page about bettas;

http://www.healthybetta.com/Care/page1-general.htm

You won't be able to tell the sex of your goldfish outside the breeding season in the early spring. During breeding season there are a few different things to look for. Yours isn't going to be in breeding condition anyway because it's under so much stress but here is a link that describes the differences in case you want to try;

http://www.bristol-aquarists.org.uk/goldfish/info/sexing-fs.htm

At Your Service;
Chris Robbins