Bubble on Goldfish head

Question
Hi Chris,

My 10 month old oranda Gold is developing a translucent bubble on her head. She is perfectly healthy otherwise. But offlate i am noticing she is a little dull.

I am in India - and its like 42 Deg Celsius here ! The fish tank water touches something like 34 Deg.C. Also - i think perhaps the water is a little too hard for them. I'm using a water softner but i am not sure if that's really helping.

I suspect the heat has a major role to play. What do you think i can do about this.

Also - should i be concerned about her bulge? If you send me you email ID - i'll send you the pic.

thanks for your help, appreciate it.
Take care,
Sam

Answer
Hi Sam;

It could be the heat that's the trouble. Goldfish prefer cooler water. I would put an electric fan near the tank to blow across the top and keep it cooler. Just be careful! (Water and electricity don't mix!) Also add air bubbles from an air pump to keep the water as oxygenated as possible. Warmer water has a lower oxygen saturation. Also make very frequent water changes and do gravel vacuuming to keep it very clean. Low waste helps the oxygen level stay higher too. All tanks need a 25% water change at least once a week with vacuuming too.

If you can upload the pic to a free hosting site such as photobucket.com and then send me the link I could take a look at it.

At Your Service;
Chris Robbins