Please help, Comet Goldfish bloody tail with white around it

[jkchefgirl]

1. How big is your tank: Gal / litres 30 Gal, EHEIM 2232 Filter for 35 Gal and 40 Gall air bubbler

2. For how long has the tank been set up: 9 months

3. How many fish: 3 Comet Goldfish and 4 Japanese trapdoor snails 2 freshwater plants and one Bamboo (just took it out)

4. What kinf of fish: Comet Goldfish

5. What are the water parameters: Ammonia.........ppm 1. 0 ppm API liquid kit
Nitrite..............ppm 0 ppm API liquid kit
Nitrate.............ppm N/A
pH.......................... N/A
Temp...............degrees Celsius / Fahrenheit 70 f

6. How often do you perform water changes: Every two weeks

7. How big are your waterchanges: .............. 25 %

8. What kind of waterconditioner are you using: Aqueon to treat the tap water and
Aquarium salt

9. Do you add beneficial bacteria: Bio Trace

10. Symptoms your fish is showing: One has a split tail right in the center to the base it is bloody then it has white around it. 2 nd fish has one small sort of fuzzy white spot on the top of its tail. The third is showing no signs. I have been doing a water changes first thing in the morning for the past 2 days taking 40 % out of the tank. I have taken the carbon out and started adding more salt, Pimafix, and Melafix. My Ammonia is not going down. I put the snails in a different tank.
My water a couple weeks ago had a brownish brackish tinge to it fish were acting normal. The Nitrite was elevated to . 25 ppm I had to move my tank so we did a 60% water change and changed the filter pad after soaking the new one in aquarium water with the old pad. Ran test on Ammonia and Nitrites reads went back to normal water was the clearest I have seen it in a long time. Now fast forward two weeks and I see my fish with the split tail reads on Ammonia is elevated. Me in panic mode.

11. Since when does your fish show these symptoms: 2 days

12. How is the normal behavior of your fish: Happy swimming around begging for food

13. How do the other fish behave: the same

14. Post pics of the sick fish:

[leebca]

Thanks for providing the information. You should be routinely taking the pH of the system and verify that the buffering ability of the water is balanced and working properly. Just an FYI.

I'd say the fish was injured. The whitish area is the healing process. However, diagnosis by Internet isn't reliable. What the fish closely. It should be improving with time. If not, post again and move the fish to a quarantine tank (if you don't have one, now is the time to invest in one).