How To Treat Bacterial Infections in Freshwater Aquarium Fish
This can be used in the fish tank, or as a bath for body sores and rotting fins and mouths. It’s a halide antimicrobial, and there’s minimal ‘resistance’ among germs to this. They made it pretty safe by complexing it with some calcium and so while the tablets are dissolving, they naturally ONLY hit 20ppm of active ingredient.
Bacterial infections are NOT CAUSED BY BACTERIA and so you have to figure out what happened, was it chilling? Handling? Mean fish picking on them? Inadequate filtration? Overcrowding?
If any of the above don’t make complete sense, or for more information on treating bacterial infections, see Drjohnson.com
You may also find the following table helpful
Bacterial Infections in Koi and Pond Fish
If you can't catch the fish and they have ulcers, consider serial treatments with potassium permanganate. This is especially good in cooler water, has a spectrum against ciliates like Costia and Chilodonella and may even destroy Fluke infestations. Dosing is better described elsewhere. See notes.
If you CAN catch the fish, consider injections of antibiotics for the valuable ones, iodine swabs on open wounds, and then water treatments (See remainder of this table) for uncatchable infected swimmers.
Scrubbing / debriding wounds in Koi depends on being able to "get through" slime and removing dead scales and NONWOVEN gauze is too slick. You need "Woven" gauze. Believe it or not, for HUMAN wounds it's undesirable. So it's CHEAPPPPPP.
Treatment with chloramine-T is potentially dangerous in the case of overdose. Dosing is beyond the scope of fish treatments website. If you're not sure about instructions in Dr Jill Spangenberg's notes, this might not be for you.
Soft rubber tanks
Aeration in the holding / bath tank
In holding, these sponge filters are soft on the Koi faces, (won't pick up eggs or fry) and they provide filtration AND aeration in one unit. They're cost-effective they BIOSEED very quickly. If you're using Lifeguard as a bath, forget bioseeding ha ha ha ha ain't no germ gonna live in the filter. Still, a soft, smushy 'airstone' is necessary.
Oxolinic acid and Naladixic acid are antimicrobials related to the quinolone antibiotics. They're 'forgiving' on dosage when mixed with oil, or other binder to put on food.
There is no contest between all of the above and injections of antibiotics. If the fish are valuable and you want top-notch results, you need to be injecting the fish with legitimate antibiotics from a prescribing veterinarian.