Important! Extremely Sick Goldfish!

Question
Hello. I am currently treating my one year old comet goldfish Skeeter for septicemia with Tetracycline. I started the treatment yesterday afternoon and gave him his second dose today. He lives in a 10 gallon tank, and I put two tablespoons of salt in his water before treatment. He has a heater in and the filter is taken out of his tank for the treatment. I read that it is common for fish to develop fin rot or ick during treatment because their immune system is not at it's best. Skeeter is developing fin rot very quickly, but I don't know what to do. It says the the Tetracycline treats fin rot also but the fin rot is developing during the treatment? He was active and eating yesterday, along with the smashing against the walls of the tank. Now he is just laying on the bottom, with fin rot, the red streaks are getting worse, and he is barely active at all. About an hour ago he started violently bashing himself against the tank again. My roommate is crying on the phone because she hates to watch it.

This fish is my baby, and I will do anything for him. Could you please help me.

Answer
Hi taylor,
I'm so sorry to hear about your goldfish. Sadly I'm afraid he may not have a chance of recovering. When fish exhibit these symptoms they are often too far gone. Most likely there is a dangerous ammonia spike, which occurs in aquariums where the "bio-filter" aka the good bacteria in the system that keep the wastes produced by the fish under control. Medications can destroy the biofilter causing pollution problems and very sickly fis. The only way to combat this during medication treatment is by keeping an aggressive water change schedule. Id recommend 50% every single day until the condition stabilizes.

Make sure all new water is close in temp to your tanks and the new water is treated with a water conditioner.

Do an immediate 50% water change.

I really hope its not too late.
Best wishes,
Susan~