Loss of scales

Question
I have two goldfish in a ten gallon tank that I have had for about a year. Not long ago, my granddaughter accidently dumped a huge amount of food in the tank and it was several hours before I caught it. I moved them, to a small goldfish bowl while I cleaned their tank from top to bottom, conditioned the water, and brought it up to the correct temperature. I then moved them, where they seemed immensely happy (they got a great new piece of furniture, a huge log house from the pet store). It was actually funny because the next morning when I went to feed them, they were just wiggling with excitement, like, "Look, Mom, what we have!" Okay, that was my interpretation, anyway. However, I noticed then that they had lost a couple scales, which I attributed to the bad tank condition. But now, about three weeks later, they have both lost several  more on both sides. I test the water frequently, and it is nearly ideal, except for being a little hard. Is this something I should be concerned about, or should treat somehow? Thank you, Jetta

Answer
What do you mean by your water is ideal? I find it very hard to believe that a 10 gallon goldfish tank will ever be ideal. They should really be in a tank 3 times that size.

You likely de-cycled your tank when you did the full clean. A full cleaning is the absolute worst thing you can do in fishkeeping. You should never take the fish out and scrub the tank down, it destroys all the beneficial bacteria that colonize it.

Do 35% water changes every other day (but do not touch the gravel  too much) for about 3 weeks. And consider upgrading your tank's size if you can.

-Nick