I’m sorry to hear that your seahorse have developed a problem. Without a culture or at least a photograph to go on, it’s very difficult to to say what is causing the cyst on your seahorse’s tail. A pimple-like lump or cyst could be an embedded parasite, perhaps the sporont stage of a protozoan multiplying within a cyst, or maybe metacercariae from digenetic trematodes, or a lesion from a bacterial or fungal infection, a granuloma, or something as simple as a little viral lymphocystis, which requires no treatment and usually clears up on its own. The topical treatment you are providing is ordinarily a good first aid measure for superficial lesions and you did well to think of it, but I would avoid it in this case; mercurochrome, Betadine, merbromin and the like are unlikely to be useful unless you are dealing with an open wound.
In my experience, those pimple-like cysts don’t respond well to topical treatments. If it is producing a puss-like substance and the seahorse is acting as if her tail is tender, my best bet right now is that it is a bacterial lesion, possibly a pyogranulatomous cyst or fistule. In that case, the best treatment would be to isolate the affected seahorse and treat her with broad-spectrum antibiotics in your hospital tank, lower the water temperature in the treatment tank to 68°F if possible to reduce the growth rate and virulence of the pathogen(s), and administer beta-glucan orally to boost the seahorses’ immune system.
If the seahorses still eating, the easiest way to get her to ingest the beta-glucan is to feed them frozen Mysis enriched with Vibrance. Both Vibrance formulations now include beta-glucan as a primary ingredient and coating the thawed Mysis with Vibrance will deliver an effective daily dose of the beta-glucan to the seahorses when they eat their daily meals.
The research on the health effects of Beta Glucan is pretty phenomenal. It has long been used in the aquaculture of commercially valuable food fishes and seafood, such as cod, turbot, salmon and shrimp. It improves the growth rate and reduces mortality rates among the fry (or larvae in the case of shrimp), and improves disease resistance in juveniles and adults. Not only does Beta Glucan help keep healthy seahorses healthy, it should also help ailing seahorses recover faster. Research indicates that it helps prevent infections and helps wounds heal more quickly (Bartelme, 2003). It is safe to use in conjunction with other treatments and has been proven to increase the effectiveness of antibiotics (Bartelme, 2003). It will be great for new arrivals recovering from the rigors of shipping because Beta Glucan is known to alleviate the effects of stress and to help fish recover from exposure to toxins in the water (Bartelme, 2003).
For more information on the potential benefits of Beta Glucan for aquarium fish, please see the following article:
Click here: Advanced Aquarist Feature Article
A simple way to drop the water temp in your hospital tank is to position a small fan so it blows across the surface of the water continually (Giwojna, Oct. 2003). This will lower the water temperature a few degrees via evaporative cooling (just be sure to top off the tank regularly to replace the water lost to evaporation). Leaving the light off on your hospital tank in conjunction with evaporative cooling can make a big difference and help you knock out this tail infection (Giwojna, Oct. 2003). Your Mustang will be fine as low as 68°F providing you drop the aquarium temperature gradually.
In a pinch, some hobbyists will even freeze plastic bottles 3/4 full of water and float the frozen bottles of water in their tank during the hottest part of the day. If necessary, that may worth trying in your case too, Michael, depending on how well your aquarium temp responds to the other measures. Don’t worry if you can’t reduce the water temperature in the treatment tank as low as 68°F — if you can just lower the water temperature a few degrees, that can make all the difference in the world when treating a bacterial infection, as we will discuss below in greater detail.
Without more information, Michael, it’s difficult to advise you as to the best antibiotic(s) to use in your case, except that they should be broad-spectrum antibiotics that are stable in saltwater, absorbed well through the skin and gills, and effective against gram-positive bacteria. But based on my past experience with bacterial lesions and tail infections, some good combinations of antibiotics to try for this problem include TMP-Sulfa combined a with Gentamicin, or as an alternative, kanamycin used in conjunction with neomycin and/or nifurpirinol.
For example, treating with neomycin in conjunction with nifurpirinol (the active ingredient in Furanase) and/or kanamycin creates a synergistic combination of antibacterials that is much more potent than any of these excellent antibiotics used alone. Likewise, TMP-Sulfa combined with Gentamicin forms in other potent synergistic combination of antibiotics that has proven to be very effective in treating pus-filled cysts on the tail of seahorses.
Trimethoprim and Sulfathiazole Sodium (TMP-Sulfa)
USE: Treatment of bacterial infections, both gram-positive and gram-negative. The combination retards resistant strains from developing. It exerts its anti-microbial effect by blocking 2 consecutive steps in the biosynthesis of nucleic acids and proteins essential to many bacteria.
DOSAGE: 1/4 teaspoon of TMP-Sulfa per 10 gallons every 24 hours with a 25% water change before each treatment. 1/4 pound (treats approx. 980 gal.)
Gentamycin Sulfate Powder 100%
USE: Probably the most powerful gram-negative antibacterial on the market today. Effective in fresh and salt water aquariums. Only 1 dose is usually required. One of the few drugs that is absorbed into the blood stream through the gills.
DOSAGE: 1/4 teaspoon of Gentamycin sulfate powder per 40 gallons of water. Only one dose is necessary. Treat one time and leave in water for 7-10 days. If water changes are done, replace the medication according to how much water was changed.
This is a potent broad-spectrum, gram+/gram- antibiotic. It is
wonderfully effective for aquarium use because it is one of the few
antibiotics that dissolves well in saltwater and that is readily
absorbed through the skin of the fish. That makes it the treatment of
choice for treating many bacterial infections in seahorses. Kanamycin
can be combined safely with neomycin to further increase its
efficacy. Like other gram-negative antibiotics, it will destroy your
biofiltration and should be used in a hospital tank only.
Nifurpirinol is a nitrofuran antibiotic that is the active ingredient
in many commercial preparations designed for use in the aquarium. It
is stable in saltwater and rapidly absorbed by fish, making it the
preferred treatment for fungal infections in seahorses (Burns, 2002).
Nifurpirinol is photosensitive and may be inactivated in bright
light, so use this medication only in a darkened hospital tank.
Nifurpirinol may be combined with neomycin (see below) to produce a
potent broad-spectrum medication that’s effective against both fungus
and bacteria. Nifurpirinol/neomycin is therefore a great combination
to use when you’re not certain whether the infection you are treating
is fungal or bacterial in nature.
Nifurpirinol is the active ingredient in many commercial medications
intended for aquarium use (e.g., Furanase, Furanace, Aqua Furan, etc.)
Neomycin is a very potent gram-negative antibiotic. Most of
infections that plague marine fish are gram-negative, so neomycin
sulfate can be a wonder drug for seahorses (Burns, 2002). As
mentioned above, it can even be combined with other medications such
as kanamycin or nifurpirinol for increased efficacy. For example,
kanamycin/neomycin is tremendous for treating bacterial infections,
while nifurpirinol/neomycin makes a combination that packs a heckuva
wallop for treating mixed bacterial/fungal infections or problems of
unknown nature. Keep it on hand at all times.
Neomycin will destroy beneficial bacteria and disrupt your biological
filtration, so be sure to administer the drug in a hospital tank.
If you cannot find these particular medications at your local fish store, most all of them can be purchased online or over the phone from National Fish Pharmaceuticals at the following web site:
Click here: National Fish Pharmaceuticals
Aside from treating your female, Michael, we also need to consider why she may have become ill and discuss how to prevent such problems in the future. With that in mind, I’m going to run through the factors that are most commonly associated with bacterial infections, and then offer some suggestions on how to minimize such health problems in your aquarium. The following information is excerpted from my new book (Complete Guide to the Greater Seahorses in the Aquarium, TFH Publications, unpublished):
Disease-causing (pathogenic) bacteria are opportunistic invaders that are normally present in low numbers but don’t cause problems until the fish is injured, stressed, infested with parasites or otherwise weakened (Indiviglio, 2002). They will then take advantage of the overtaxed seahorse’s impaired immune system and reproduce extremely quickly, causing a variety of illnesses and problems (Basleer, 2000). Some of these are specific to seahorses, such as snout rot and white tail disease, and others are common to all fishes, such as Mycobacteriosis or popeye.
A bacterial infection almost always indicates that there is another problem that is stressing the fishes and weakening their immune response (Indiviglio, 2002). In addition to treating the infection itself, the hobbyist must also identify and correct the underlying problem in order to restore health. Check your water quality and aquarium parameters. A water change and general clean up are usually a good place to start.
One of the best ways to prevent bacterial infections and other disease problems is to provide them with a stress-free environment. Many of the parasites and pathogens that plague our pampered ponies are ubiquitous — present in low numbers in most everyone’s systems or within the seahorse’s body itself (Indiviglio, 2002). As a rule, healthy fish resist such microorganisms easily, and they only become a problem when seahorse’s immune system has been impaired, leaving it susceptible to disease (Indiviglio, 2002).
Chronic low-level stress is one of the primary factors that suppresses the immune system and weakens the immune response, opening the way to infection and disease (Indiviglio, 2002). Long-term exposure to stressful conditions is very debilitating. Among other effects, it results in the build up of lactic acid and lowers the pH of the blood, which can have dire consequences for seahorses for reasons we’ll discuss later.
When disease breaks out in an established aquarium it is therefore generally an indication that something is amiss with your aquarium conditions. A gradual decline in water quality is often a precursor of disease (Indiviglio, 2002). Poor water quality is stressful to seahorses. Prolonged stress weakens their immune system. And an impaired immune system leaves the seahorse vulnerable to bacterial, viral, and fungal infections to which healthy, unstressed seahorses are immune. As if that weren’t bad enough, there are a number of environmental diseases that are caused directly by water quality problems.
With this in mind, it’s important to review the most common stressors of captive seahorses. These include the design of the aquarium itself. A poorly designed seahorse setup that lacks adequate cover and shelter, or has too few hitching posts, will be stressful to the occupants (Topps, 1999). Seahorses are shy, secretive animals that rely on camouflage and the ability to conceal themselves for their safety and survival. A sparsely decorated tank that leaves them feeling vulnerable and exposed will be a source of constant stress (Topps, 1999). The seahorse setup should have plenty of secure hiding places so they can conceal themselves from view completely whenever they feel the need for privacy. It should be located in a low traffic area away from external sources of shock and vibration.
Needless to say, rapid fluctuations in temperature, pH, salinity and other aquarium parameters must also be avoided. A large aquarium of 40 gallons or more provides much greater stability in that regard than does a smaller setup. The greater the water volume in the aquarium and sump, the more stable the system will be.
Heat stress is especially debilitating and dangerous for seahorses due to a number of reasons (Olin Feuerbacher, pers. com.). For one thing, elevated temperatures can have a very detrimental effect on the immune system of fishes. This is because many of the enzymes and proteins involved in their immune response are extremely temperature sensitive (Olin Feuerbacher, pers. com.). Some of these protective enzymes can be denatured and inactivated by an increase of just a few degrees in water temperature (Olin Feuerbacher, pers. com.). So when seahorses are kept at temperatures above their comfort zone, their immune system is compromised and they are unable to fend off diseases they would normally shrug off.
At the same time heat stress is weakening the seahorse’s immune response, the elevated temperatures are increasing the growth rate of microbes and making disease organisms all the more deadly. Research indicates that temperature plays a major role in the regulation of virulence genes (Olin Feuerbacher, pers. com.). As the temperature increases, virulence genes are switched on, so microorganisms that are completely harmless at cooler temperatures suddenly become pathogenic once the water warms up past a certain point. Thus both the population and virulence of the pathogens are dramatically increased at higher temperatures (Olin Feuerbacher, pers. com.).
This is true of Columnaris and certain types of Vibrio, which is one type of bacteria that is often involved and tail infections. At cool temperatures these bacteria are relatively harmless, but at elevated temperatures they become highly contagious, virulent pathogens that kill quickly.
In short, it’s doubly important to keep seahorses at the proper temperature. Because of the reasons mentioned above and the fact that water holds less and less dissolved oxygen as it warms up, seahorses generally tolerate temps at the lower end of their preferred range much better than they handle temperatures at the upper limit of their range.
Incompatible tankmates are also stressful for seahorses. This includes not only aggressive, territorial fishes and potential predators but also inoffensive species that are restless, active fishes. Seahorses may be uneasy around fishes that are always on the go, swimming tirelessly back and forth.
Other common stressors for seahorses include overcrowding, overfeeding, stray voltage, and a host of issues related to water quality: ammonia or nitrite spikes, high nitrate levels, inadequate circulation and oxygenation, high CO2 levels and low 02 levels, low pH, etc., etc., etc (Giwojna, Jun. 2002).
In short, if hobbyists provide their seahorses with a stress-free environment, optimum water quality, and a nutritious diet, they will thrive and your aquarium will flourish with a minimum of problems. Preventing disease in the first place is infinitely preferable to trying to treat health problems after the fact. Good seahorse husbandry and diligent maintenance will be rewarded; sooner or later, negligence and poor aquarium management will be punished.
When disease breaks out in an established aquarium it is therefore generally an indication that something is amiss with your aquarium conditions. A gradual decline in water quality is often a precursor of disease (Indiviglio, 2002). Poor water quality is stressful to seahorses. Prolonged stress weakens their immune system. And an impaired immune system leaves the seahorse vulnerable to bacterial, viral, and fungal infections to which healthy, unstressed seahorses are immune.
At the first sign of a health problem:
Because diseases are so often directly related to water quality, or due to stress resulting from a decline in water quality, when trouble arises the first thing you should do is to break out your test kits and check your water chemistry. Very often that will provide a clue to the problem. Make sure the aquarium temperature is within the acceptable range and check for ammonia and/or nitrite spikes first. See if your nitrate levels have risen to harmful levels and look for a drop in pH.
Be sure to check your dissolved oxygen (O2) level too. A significant drop in O2 levels (6 – 7 ppm is optimal) is very stressful yet easily corrected by increasing surface agitation and circulation to promote better oxygenation and gas exchange. At the other extreme, oxygen supersaturation is a red flag indicating a potentially deadly problem with gas embolisms (Gas Bubble Syndrome).
If any of your water quality parameters are off significantly, that may well be the cause of the problem or at least the source of the stress that weakened your seahorses and made them susceptible to disease. And correcting your water chemistry may well nip the problem in the bud, particularly if it is environmental, without the need for any further treatment.
Clean Up & Perform a Water Change
After a quick check of the water chemistry to assess the situation, it’s time to change water and clean up. In most cases, the surest way to improve your water quality and correct the water chemistry is to combine a 25%-50% water change with a thorough aquarium clean up. Siphon around the base of your rockwork and decorations, vacuum the top 1/2 inch of the sand or gravel, rinse or replace your prefilter, and administer a general system cleaning. The idea is to remove any accumulated excess organic material in the sand/gravel bed, top of the filter, or tank that could degrade your water quality, serve as a breeding ground for bacteria or a reservoir for disease, or otherwise be stressing your seahorses. [Note: when cleaning the filter, your goal is to remove excess organic wastes WITHOUT disturbing the balance of the nitrifying bacteria. Do not dismantle the entire filter, overhaul your entire filter system in one fell swoop, or clean your primary filtration system too zealously or you may impair your biological filtration.]
At first glance your aquarium parameters may look great, but there are some water quality issues that are difficult to detect with standard tests, such as a decrease in dissolved 02, transitory ammonia/nitrite spikes following a heavy feeding, pH drift, or the gradual accumulation of detritus. A water change and cleanup is a simple preventative measure that can help defuse those kinds of hidden factors before they become a problem and stress out your seahorses. These simple measures may restore your water quality and correct the source of the stress before your seahorse becomes seriously ill and requires treatment.
In short, my recommendation would be to treat your female with a broad-spectrum combination of antibiotics, continue to administer beta-glucan orally, and decrease the temperature in your hospital tank as much as possible. Reducing the water temperature and cooling down the microbes will slow down their metabolism and rate of reproduction
accordingly, and give the seahorse’s immune system a better chance to fight off the disease (Giwojna, Oct. 2003).
While your female is being treated in isolation, you can take appropriate measures to rehab your main tank in order to assure that your male Mustang remains unaffected and that your female has a healthy aquarium to return to what she has recovered.
Best of luck treating your female scale problem, Michael! Here’s hoping she’s as good as new before you know it!