goldfish scales

Question
Hi!  I have had 2 fantail goldfish for about 3 months.  I have noticed their scales changing.  One fish is brown, and a few of his scales now look silver.  The other fish is white, and it looks like a few of his scales have fallen off, because I can see dull skin where all around is shiny scales.  Do you know what could be causing these changes in their scales, and is there anything I can do to help them grow healthy scales?
Thanks,  Karina

Answer
Hi Karina;

There are a few reasons why goldfish will lose scales;

Fighting or breeding behavior. Male fish will chase the females to breed with them. Sometimes they scrape themselves on things. Some goldfish can be a bit aggressive with others and bite each other

Water quality problems can cause scale loss and inflammation. Keep the water very clean by changing 25% of the water every week and vacuuming the gravel. If the tank is too small the fish will be stressed from overcrowding because the water quality will not be very good. Goldfish need 10 gallons per fish in order to thrive.

Sometimes fish will "scratch" themselves by rubbing their bodies on the bottom of the tank or on decorations. It is called "flashing" and is usually caused by parasites or toxins in the water. Their skin is irritated and/or burning in either case and they are trying to rub off whatever is hurting them.

Be sure the tank is big enough and clean enough for them and hopefully they will feel better soon. Watch for spots, dots and other abnormalities.

I hope they feel better soon...

At Your Service;
Chris Robbins