1. Acriflavin
2. Betadine
3. Copper Sulfate
4. Furanace, Furoxone, Nitrofurazone
5. Malachite Green
6. Oxolinic Acid
7. Potassium Permanganate
8. Tea Tree Oil

Reference: Herwig, Nelson. 1979. Handbook of Drugs and Chemicals used in the Treatment of Fish Diseases: A Manual of Fish Pharmacology and Materia Medica. Springfield, Illinois: Charles Thomas

Also, oregano oil can be used (it's pretty much the strongest anti bacterial known, even killing human MRSA when no other antibiotic will, an even in very low doses), but would need to be emulsified with alcohol. "Almond" leaves and the berries of the black alder tree also have becteriostatic effect, as does peat moss.

Certain fruits have compounds in them that kill bacteria: "The results obtained with Pseudomonas aeruginosa was particularly interesting, since it was inhibited by clove, jambolan, pomegranate and thyme extracts. This inhibition was observed with the individual extracts and when they were used in lower concentrations with ineffective antibiotics." See: http://www.scielo.br/scielo.php?pid=S1517-83822000000400003&script=sci_arttext