Fantail problem, perhaps?

Question
I have two large fantails that lived outdoors this past summer, but I brought them inside into a 29-gallon aquarium so I could see them more often. They have been inside with a black moor, a pleco, two other nondescript feeder goldfish that I thought were too pretty to get eaten, and 2 albino African clawed frogs. My problem is, a few of the scales on the fantails seem to be more prominent and shiny, and one looks as if she is scratching against a rock, although I can't tell for sure. It doesn't look like ich or fungus or any other type of lesion I have seen pictures of on the net, just a few shiny scales, and they are very healthy otherwise. My tank pH is 7.4 and 72 degrees, but I don't add much aquarium salt due to the frogs. I added some stuff to clear the ammonia with my last water addition. Are these shiny, prominent scales anything to worry about? Oh, it doesn't look anything like dropsy either. Thanks in advance!

Answer
Hello Becky-

As long as your fish are not showing other symptoms, this is most likely natural coloration/scale formation.

Perhaps your fantails had parents that were pearl-scale fantails? These fish have naturally shiny, protruding scales, and if your fish are mixed breeds, the placement of the "special" scales can vary.

Check here for some pearl-scale pictures:
http://www.aquariumfish.net/images_01/pearlscale_crown_calico_w270.jpg
http://www.goldfishparadise.com/images/pearl.jpg

Hope this is useful!
-Amber Worman