Maracyn II cause lethargy?

[guitarfish]

Hello everyone,

I have a small yellow tang in a 20g QT. He's been in hypo for 32 days because he had ich. At about day 28, he started looking bad and had some red streaks, so I got some saltwater Maracyn II and added it according to the directions. The streaks cleared up after a day or two, I am finishing the full 5 day treatment tomorrow.

My concerns - the tang is pretty lethargic, and eating about 1/4 of what he used to. He hangs out in a corner mostly. His breathing is normal. I've done 25% water changes every 2-3 days over the last week or so, and all water parameters are normal - aside from being yellow.

I was wondering if the tang's behavior might be a result of the meds?

 

[Rondelet]

Oxytetracycline is one of the most commonly used antibiotics used in farmed fish and it appears to be tolerated well when administered orally. Minocycline, which is the active ingredient in Mararcyn II (SW and FW) is related - both are tetracyclines. In mammals, a common side effect with orally administered tetracyclines is irritation to the gut and intestinal tract. This is because the drug can modify the composition of the gut flora disrupting normal functioning. In people this is often seen as nausea, vomiting and diarrhea. It's possible, although very had to say for certain and just a guess really, that your Tang may be reacting negatively to the drug since they are for a large part herbivorous fish with complex micro flora in their gut. If the treatment is completed, you might consider using a carbon filter to strip the excess minocycline from the water and see if this helps get your fish back on to regular feeding and starts to perk up.

Although, I also suspect being in Q for a long time and in hyposalinity may be a contributing factor as this may be adding a certain degree of stress to the fish. This could easily put the fish off feed, make it appear lethargic and generaly appear sick. In fact, it's possible that this is why it contracted what appeared to be a bacterial infection at day 28. Just my thoughts.

Hope this helps.

 

[kevin2000]

You might consider adding some live brine shrimp to "jump start" his appetite. Its not unusual for fish who are sick to start to eat less .. whats important is to keep them from "not eating" period. While LB isn't necessarily the best nutritional food it is one of the most appealing foods and once the fish has started to eat more you can focus on nutrition.