Sick Ranchu

Question
It has been a week since I have my ranchu in a separate 10 gallon tank.  He's been having an open sore on his side.  I thought it was a parasite problem so I have been treating him with 10 drops of Formalite III every other day.  Two days ago he developed another sore near his tail so I stopped all treatment, changed about 90 percent of the water and added 10 tsps of non iodined salt.  I have not fed him in 2 days.  Also today I have cleaned the wounds with hydrogen peroxide and applied antibiotic.  Should I treat him with Maracyn 2 or wait?  I'm also testing for ammonia level in the main tank right now and will test for the pH and nitrate soon.  The other fishes in the main tank seem fine but I am seeing a few red spots and white spots and one oranda has some white fuzz growing on his head.  This is my husband fish tank, he boasts to have the best filtration system money can buy but I know better.  I feel sorry for his fish.  I just put about 70 tsps of salt in his 70 gallon main tank.  Anyway right now I'm worry about the ranchu in the hospital tank most, please help me.  I feel personally responsible for him and have grown attached to him.  I really appreciate your help.

Answer
Hi Di;

Redness usually indicates a bacterial infection. I would hit it with some "Maracyn Two". It's a fish antibiotic available at most fish stores or pet sections in department stores. Also pick up some Melafix to help heal the wounds and soothe the sore spots.

It sounds like the bacterial infection has affected the other fish too. The one with fuzzy head may have a fungus too, but bacterial infections can look like fungus. The bacteria and fungal populations in the water can be reduced in the main tank by making water changes of 25% two or three times a week for the next week or two. It will help avoid spreading it further. Add more salt to the fresh new water only. For instance, you will be replacing 30 to 35 gallons for a 25% change, so add back 30 to 35 teaspoons of salt every time. You can medicate with the maracyn two and melafix there too if it looks like they need it.

If your main tank has not been maintained weekly with a 25% water change, even the most fancy filtration in the universe isn't going to keep your fish healthy. Every filter leaves behind an organic waste called "nitrAte" (not nitrIte, it's different). The only way to remove it from our fish tanks is through weekly 25% water changes and gravel vacuuming. Keeping Nitrate below a level of 20 ppm is very healthy. Fresh new water also adds back important electrolytes and trace elements that are used by the system and the fish over time and keeps the water chemistry consistent. Your filter can't do any of that. It just processes the waste and puts out nitrate as a by-product. Here is a good article that explains it in more detail if you need more information;

http://www.aquarticles.com/articles/management/greco_water%20changes.html

Something else I was just thinking about that you might check is water temperature. Goldfish are coldwater fish. If your tank is higher than 72f on a long-term basis turn down it's heater if it has one, or simply remove it. When they are kept too warm they become weak and prone to disease.

Let me know if you need more help. Followups welcome...

At Your Service;
Chris Robbins