prophylactic antibiotic treatment for quarantined fish

[pandadoc]

Hi Lee,

I have read your posts regarding quarantining of new fish and I know that you prescribe prophylactically treating certain fish for potential diseases such as Tangs for Ick, wild caught clowns for Bookynella, etc. If I have quarantined fish that did not go through a fresh water/methylene blue dip, would you recommend prophylactic treatment with a broad spectrum antibiotic such as Maracyn II? I have a pair of cross hatch triggers and a rhomboid wrasse that I have been holding in quarantine for 4 weeks now that have not shown any signs or symptoms of disease, however, I want to be extra cautious before introducing them into the display tank in another 2 weeks.

thanks for your input in advance!

[leebca]

The FW dip was and isn't to affect bacteria. It is to dissuade certain parasites (not bacteria) that 'hide' on the fish's body and gills. It actually kills many of these outright.

The misuse and abuse of antibiotics can create problems. For instance, antibiotics fight specific kinds of bacteria. The example of Maracyn Two for instance. It's not broad spectrum. It fights certain kinds of bacteria. Also, its specialty is fighting systemic infections. There are others that are effective against topical infections, and then only by certain bacteria. So, the complexity of their value/targets makes a prophylactic use likely to fail.

Next consideration is that there are such things as 'good' bacteria. Right? The marine fishes we keep in captivity use bacteria in their intestinal tracks to help with digestion and the making of vitamins. The careless use of antibiotics can and do disrupt this. So a fish uninfected can be harmed by the use of certain antibiotics. Likewise, some antibiotics disrupt the biological filter, causing bad water quality, which for a healthy fish, could kill it. So there are scenarios that can actually do more harm than good.

The use of antibiotics is to help a fish overcome an infection of pathogenic bacteria -- not to harm the fish or cure the disease. But sometimes antibiotics do harm the fish and their use should be weighed against any harm they will do considering their benefit. So in the case of there being no need for its use, there is not any upside to their use. Thus there is no prophylactic benefit.

Bottom line after considering the above -- we don't want to use antibiotics like this.

To be extra cautious is to your credit. Good job! But let's make that a reality without thinking about treatments: Keep your fish in quarantine for the full 6+ weeks. Watch them/monitor them closely. Treat only what you find needs treatment (exceptions for prophylactic treatments noted). Make it a point to get to know the fish so well and to be so close to them that you can 'tell' when they are not well. That is: put in the extra time to watch the new fish; spend time (one of your most valuable resources) with the fish. Don't release them into the DT system until you know they are healthy and disease free AND eating prepared foods.

[pandadoc]

Thanks for your input, Lee! I will continue to monitor my quarantined fish for any signs or symptoms. I will not use any antibiotics unless indicated to treat disease. The fish are eating well, three times a day. I supplement their varied diet with vitamins and essential fatty acids. I took your advice and de-wormed them using both Praziquantal and Metronidazole and I am performing daily (or every other day) water changes while keeping ammonia and nitrites in check.

[leebca]

You're welcome! Good job!