Two gold fish about 7 years old in a 30 gallon tank with one small algae eater. I did
not do my research and changed the tank - new tank, new filter but did keep about 50% or a little more of the old water. I did not realize what had happened for about a month. Bought quick dip test strips and found out. Now I have one fish back to near normal but the smaller one has white spots, red streaks in his tail, and now red around one gill. His appetite is very good. I have taken out the carbon in the filter. Added an Ick treatment, also Melafix daily for the last 5 days. I have a nitrasorb sand thing in the filter to try to get the nitrates down. I am changing 15% of the water every day, adding a slime coat treatment and something that takes out the chlorine. I let the water sit 24 hours. The water continually tests at 200 ppm for nitrates, .5 to 3.0 for nitrites, hardness is 300 ppm, alkalinity if 80ppm, pH has been neutral. ammonia is fine. I did add a small amount of salt to the water when I started working on the tank. Both fish eat well and are acting normal.

Thanks Karen

Greetings and welcome to the board!


Try bumping up the amount of water you change to 30-40% This
will bring down the nitrItes and should help out with the nitrAtes.
This will help with the red streaks in the tail area.

What are the water param readings for your tap water?