Help Please! Cannot Identify Problem W/ Platy

[alfiethefish]

Thank you! I've done major water changes, and today I finally got a nitrite reading of 0! I will be checking it daily. Thanks everyone for your help.

 

[Colin_T]

Do a 75% water change every day until the ammonia and nitrite levels are 0ppm.
Make sure any new water is free of chlorine/ chloramine before it is added to the tank.

I reiterate what I wrote in post #13.