Help! Quick!

[GouramiGirl87]

My Goldfish is dying, the nitrite levels have been high, but actually went down in the last few days
It has been just floating around acting like it is going to die! My algae eater keeps attacking it and sucking on it. I feel horrible! It is a 20 gal tank with a penguin filter and it is only the goldfish and algae eater. yes i know they tend to not like algae and suck on the goldfish.
HELP!!!!

 

[black angel]

You have to seperate the fish or the goldie will die from the attacks from the plec.
What are your readings for ammonia, nitrite, nitrate and ph?
As the nitrites were high it sounds like the ammonia was as well so keep doing really large water changes each day to get everything back to where they should be and add 1 level teaspoon per gallon of aquarium salt to the tank.