Ok I been beating myself over this fish tank since it was given to me.
First let me begin with this. My Goldfish was fine before I added a Pleocostomus and Red-tailed black shark I believe four days ago. Yesterday I saw a red rash on my gold fish belly that has some dark red mixed in it due to his scales being dark I believe. He is a brown/black gold fish. He is eating just fine and is Trolling the shark ever since he got put in the tank with him. The gold fish is bigger by two inches. Now they have not been fighting but the goldfish ate some of the other fishes food though when I first started feeding them. I now hide the other fishes' food so the gold fish can't get to it.
Now I have waited one day to see how the Gold fish does so far he is doing great and he is being active but still Trolling
the shark, but he has been laying on the bottom of the tank a lot today (but normally he does this but not as much as he use to since my other Gold Fish died MONTHS AGO) So yes normally he is at the bottom just chillen under the filter but he has been doing a lot today. Speak of I will check on him now.....
Ok he is laying in the corner bottom of the tank under the filter. He is not very active right now.
Any ideas what is happening to my little guy. I don't want to loose him because of added some **** fish to the tank.
Oh yeah I did clean the tank about a week ago to ten days. Taking most of the water out leaving about 30% of the old water in there. then a few days after cleaning we got new fishes and added their water into the Gold Fish's water in the 5.5gal tank
Any questions you have for me please ask me so I can give you more detail of the problem. I will try to take a photo but he doesn't like showing his belly to me right now since I had to handle him to see what it was in the first place.
Please I need as many people answering this for me. I need help before I hate myself for ever getting fish.