Dear Diane:

Pete Giwojna

Dear Diane:

I’m very sorry to hear about this sudden development with Galene, Diane. I know you have given her superb care right from the first and I’ve been fascinated by the amazing dancing ability she has developed under your conditioning and how responsive she has become to the music!

But it’s very difficult to determine what may be wrong when there are no premonitory symptoms of an illness or any signs of an underlying health problem to point the way to the correct diagnosis. Right now the only thing I can say for certain is that Galene was apparently perfectly healthy yesterday and is now in great distress for reasons that are unclear and unknown…

I don’t think that transferring Galene to your hospital tank and treating her with broad-spectrum antibiotics is necessary the best approach to this problem, Diane. Being handled, separated from her tankmates, and transferred to a Spartan quarantine tank amid strange surroundings would be very stressful for Galene, and the last thing we want to do right now is to increase her level of stress. I would try treating the main tank with metronidazole first, as explained below, and if you don’t see clear signs of improvement within three days, then you can resort to antibiotics in the hospital tank, Diane. That would by you time to get the treatment tank up and running and to line up any meds you may need.

A sudden loss of appetite, rapid respirations, and darkening in coloration are all clear indications of stress, but they can be associated with so many different types of problems that they don’t really reveal much about what may be going on. For example, rapid respirations are often associated with gill flukes and protozoan parasites that attack the gills, but rapid breathing can also result from a spike in the nitrogenous wastes (e.g., ammonia, nitrate, or nitrates), which can cause hemoglobin to be converted into a form of the molecule (methhemoglobin) that is unable to transport oxygen, and panting can also be a sign that the dissolved oxygen levels in the aquarium water are too low (or the CO2 levels are too high), and rapid respiration is also associated with stress in general.

If there had been a spike in the ammonia, nitrite, or nitrate levels, or an outbreak of parasites in the aquarium, or if the dissolved oxygen levels were too low or the levels of dissolved carbon dioxide were too high, all of the seahorses in the aquarium would be affected to one degree or another, and that’s not the case in this incident, Diane.

We know you’re water quality parameters are optimal, so for now I’m going to concentrate on Galene’s loss of appetite instead. One thing that can cause a seahorse to go off its feed with no outward indications of a problem is internal parasites, especially intestinal flagellates, which are normal intestinal flora that are naturally found in the gastrointestinal tract and reproductive system of fish in low numbers. They only cause a problem when their numbers get out of control, which can happen for a number of reasons, including chronic stress, and it’s quite possible for only one seahorse to be so affected.

Metronidazole is a very safe medication that can control such internal parasites, and which can be used to treat Galene in the main tank where she is the most comfortable. It won’t harm the biofilter or disrupt the biological filtration and it is perfectly safe for seahorses, so it’s a form of treatment that may be helpful in a case like this and will not increase the stress level for Galene.

Metronidazole is very effective in treating intestinal flagellates and other internal parasites, which are the most common cause of loss of appetite in otherwise healthy seahorses, and it can be safely used in the main tank since it will not damage the beneficial nitrifying bacteria that perform biological filtration.

It’s a good antiparasitic that is is perfectly safe to use in a typical seahorse tank, although you may want to relocate sensitive invertebrates such as decorative shrimp or starfish during the treatment period. You’ll need to remove activated carbon and other chemical filtration media beforehand, and turn off UV sterilizers or ozone generators when treating the tank with this medication.

Here is some more information explaining how to use metronidazole to treat problems such as this, Diane:

Intestinal Flagellates

Intestinal flagellates are microscopic organisms that move by propelling themselves with long tail-like flagella (Kaptur, 2004). Such flagellates can be found in both the gastrointestinal and reproductive tracts of their hosts. In low numbers they do not present a problem, but they multiply by binary fission, an efficient means of mass infestation when conditions favor them (such as when a seahorse has been weakened by chronic stress), Kaptur, 2004. When they get out of control, these parasites interfere with the seahorse’s normal digestive processes such as vitamin absorption, and it has difficulty obtaining adequate nourishment even though it may be eating well and feeding heavily (Kaptur, 2004). Suspect intestinal parasites are a work when a good eater gradually wastes away despite its hearty appetite (Giwojna, Dec. 2003). Their presence can be confirmed by examining a fecal sample under a microscope, but they can be easily diagnosed according to the more readily observed signs described below (Kaptur, 2004).

The symptoms to look for are a seahorse that’s losing weight or not holding its own weight-wise even though it feeds well, or alternatively, a lack of appetite accompanied by white stringy feces (Kaptur, 2004). When a seahorse stops eating aggressively and begins producing white, stringy feces instead of fecal pellets, that’s a clear indication that it’s suffering from intestinal flagellates (Kaptur, 2004). Treat the affected seahorse(s) with metronidazole at the first sign of either condition (Giwojna, Dec. 2003).

Metronidazole is an antibiotic with antiprotozoal properties that is very effective in eradicating internal parasites in general and intestinal flagellates in particular (Kaptur, 2004). It is ideal for this because it is rapidly absorbed from the GI tract, has anti-inflammatory effects in the bowel, and was designed specifically to treat protozoal infections and anaerobic bacterial infections by disrupting their DNA (Kaptur, 2004).

When administered properly, metronidazole is wonderfully effective at eliminating intestinal parasites, and there should be signs of improvement within 3 days of treatment (Kaptur, 2004). The seahorse’s appetite should pick up, and as it does, those characteristic white stringy feces will return to normal (Giwojna, Dec. 2003).

Intestinal parasites are typically transferred from their host to uninfected fishes by fecal exposure, and good tank management and hygiene can therefore go a long way towards limiting their spread (Giwojna, Dec. 2003). You don’t want seahorses eating frozen Mysis that may have become contaminated from laying on a dirty substrate (Giwojna, Dec. 2003). Using a feeding station can help prevent this as can vacuuming the substrate regularly.

Fortunately, intestinal flagellates have virtually no ability to survive outside their host’s body (Giwojna, Dec. 2003). If you detect the problem early and are diligent about cleaning the substrate while the affected seahorse is undergoing treatment in isolation, the parasites should be easily eliminated from your system and chances are good the rest of your herd will remain unaffected (Giwojna, Dec. 2003).

If the seahorse is still eating, administering the metronidazole orally via medicated frozen Mysis is often extremely effective (Giwojna, Dec. 2003) in resolving the problem and restoring the seahorses appetite.

If the problem is due to intestinal flagellates and other internal parasites, it may respond positively to the metronidazole and show improvement within a few days.

Okay, Diane, that’s the rundown on using metronidazole to treat intestinal flagellates and other internal parasites that are commonly associated with a loss of appetite. In your case, you would need to add the medication to the main tank, since Galene is no longer eating.

That’s what I would recommend you try, particularly if you have noticed that Galene’s is now producing white, stringy feces rather than her normal fecal pellets. Metronidazole can also be helpful on the off chance that gill parasites of some sort may be contributing to the problem.

Metronidazole is an antiparasitic that is commonly used to treat problems such as Hole-in-the-Head disease (Hexamita), Chilodonella (body slime), freshwater ich, Malawi bloat (internal Hexamita), Epistylis in pond fish, intestinal flagellates and other internal parasites in aquarium fishes. Your best bet is to call around to the local fish stores and pet stores in your area, and ask them if they carry a medication with metronidazole as the primary ingredient. (It may not be sold as “metronidazole” by name — it may be sold under a brand name instead, such as Flagyl, Hexamit, Hikari Metro+, Seachem Metronidazole Aquarium Fish Medication, or Metro-Pro, all of which are medications with metronidazole as the active ingredient. Any such medication will do nicely.)

Your local fish store should carry a medication designed for aquarium use whose primary ingredient is metronidazole (e.g., Flagyl, Metro-MS by FishVet, Hexamit, Seachem Metronidazole, etc.). Just follow the instructions on the package and be sure to use the marine dose. Temporarily relocate sensitive invertebrates such as decorative shrimp and starfish until after the treatment regimen has been completed.

The only other thing I would suggest is to make sure that your seahorse tank has plenty of surface agitation and aeration to promote more efficient gas exchange at the air/water interface, Diane. That will help to make sure that your dissolved oxygen levels are nice and high and that the levels of dissolved carbon dioxide are low, which may help Galene to breathe easier in the meantime.

The methylene blue is a good thought and is worth a try, but it can’t be used in the main tank and I don’t know if Galene could tolerate a dip right now, so use your own judgment about that.

Best of luck resolving this problem, Diane.

Pete Giwojna, Ocean Rider Tech Support

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