GUPPIES LOSING COLOR AND DIE

Question
WHAT have I done wrong?
I have a 10 gallon tank and I used aquasafe from Tetra Aqua when the water was changed I checked the chemicals and the only thing on the test stick that was even a little high was the waterhardness?
these guppies swim around like nothing is wrong until you watch them closely then I saw that they were swimming next to a hard little no fishing sign in the tank and after that they dive at it and rub there sides against it?

all of them are doing this is this normal?
this tank has two males and three female guppies and one algae eater and one small goldfish.

so far I have lost two male guppies and I am confused.
PLEASE HELP!! My mom gave this tank to my daughter and she is 8
and of course she has named every fish in the tank.

Answer
Hi Matt,
 It is possible that the fish have ick, which is a common disease. The most likely source is the goldfish.  You should never put goldfish in with tropical fish because goldfish are notorious for carrying various infectious diseases, particularly ick.   You can treat ick with any of the commercially available anti-ick products, such as Rid-Ick or Quik-Cure.   You should do water changes (about 25%) every other day to help the situation.

-- Ron
  rcoleman@cichlidresearch.com
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