This extremely helpful article includes some very pertinent information regarding antibiotic use including a detailed run-down of types of bacteria, the best ways to combat bacteria, appropriate treatment regimens, routes of administration, risks and consequences of antibiotic use, etc.
This link includes detailed information on the specific uses, ideal modes of administration, and potential side effects of many commonly used antibiotics. This is important information for you when selecting the best medication.
At the bottom of the page there is also a dosing chart including the best mode of administration, bath dosage, and ORAL dosage. For those who soak foods, this is very pertinent, as too high or too low a concentration can be detrimental to treatment. Oral dosing is MUCH more effective than bath treatments in many instances.
RE: Use of Antibiotics in Ornamental Fish Aquaculture
I used quite a few medication on my Neon Rainbowfish when they came with mouth rot. It took 3 different antibiotics and a few general purpose medications to finally cure them. I spent more on the medications than the fish themselves.