I have recently added a small black moor (about 5cm/2inches) to my approx 40gallon aquarium. I have three other fish, all of which seem well. In the few days (I bought him on Sunday) since I got him, he appears to have developed what I think is fin rot... or perhaps a fungus? He has a whitish coating on small parts of his tail, as well as on his abdomen. He is also clamping his fins some of the time. He is eating well.
Test Results for the Following:
* Ammonia Level(Tank): 0
* Nitrite Level(Tank): 0
* Nitrate level(Tank): about 3 ppm (our scale has 0, the next level is 5ppm... it is less than 5 but not 0)
Other Required Info:
* Brand of test-kit used and whether strips or drops? API using drops
* Water temperature? usually around 24 degrees Celsius (75 degrees Fahrenheit), but gets as hot as 26 degrees.
* Tank size (how many gals.) and how long has it been running? 40gals, been running 8 months.
* What is the name and "size of the filter"(s)? Aquamantra IFXE200 with spray bar
* How often do you change the water and how much? twice per week, about 1/5th.
* How many days ago was the last water change and how much did you change? water changed 3 days ago, 1/5th.
* How many fish in the tank and their size? 4 fish, all small goldfish about 5cm - 6cm..
* What kind of water additives or conditioners? API Tap Water Conditioner
* What do you feed your fish and how often? Mostly blood worms and flakes. Twice per day, small amounts no more than they can eat in one minute.
* Any new fish added to the tank? yes, the sick black moor.
* Any medications added to the tank? no.
* List entire medication/treatment history for fish and tank. Please include salt, Prazi, PP, etc and the approximate time and duration of treatment. Never treated.
* Any unusual findings on the fish such as "grains of salt," bloody streaks, frayed fins or fungus? White skin in patches.
* Any unusual behavior like staying at the bottom, not eating, etc.?
It may also be worth noting that I recently added the drift wood after soaking for several weeks.
We have the light on all day long, from 8am to about 6pm.
One of the plants is also new.
Other fish seem well, except the white and orange fish may also now have a small area of the same white patch - but he seems very active and well. I am not sure if these photos will work: