Re:Treatment of possible Vibriosis

Pete Giwojna

Dear Heather:

Okay, it sounds as though your female Sunburst definitely has an infection of some sort. As I mentioned earlier, various protozoan parasites attack the skin, and the damage to the integument that results allows secondary bacterial and/or fungal infections to develop, resulting in pale patches and irregular irregular areas of depigmentation. That could be what we are dealing with here or it could be a primary bacterial infection or a mixed infection that is responsible for the white patches. In any case, we need to isolate your female Sunburst and begin treatment as soon as possible before the infection advances to the point where there is tissue erosion and ulceration of the affected area.

It’s very difficult to say which particular infection may be involved in this case without any lab tests, but the appropriate treatment would be to administer broad spectrum antibiotics in a hospital tank in conjunction with a series of formalin baths, and to lower the water temperature in the treatment tank to 68°F-72°F to reduce the virulence and growth of the infection.

Unfortunately, Heather, none of the medications that you have on hand right now will be useful in treating the problem of this nature. The antibiotics I would recommend for handling this sort of problem are Baytril (which you probably will not be able to obtain), Neo3 or a combination of neomycin and/or kanamycin plus triple sulfa used together, or else Furan2 combined with acriflavine, as discussed below.

Baytril is a potent new broad-spectrum antibiotic that is effective against both gram-negative and gram-positive bacteria and is widely used to treat marine fish. However, it is a prescription medication and you would need to obtain it from a veterinarian. A 7-day treatment regimen for the liquid form of Baytril is recommended as follows:

Day 1: a five hour bath in Baytril at a concentration of 22.7 mg/ml.
Day 2: perform a 50% water change in the treatment tank and administer a 5-hour bath in Baytril at half strength (11.4 mg/ml).
Days 3-7: repeat the procedure for day 2 — a 50% water change followed by a five hour bath in Baytril at a concentration of 11.4 mg/ml.

If you cannot obtain Baytril, then treating the seahorse with Neo3 or else a combination of kanamyacin and/or neomycin used in conjunction with triple sulfa, or alternately, Furan2 combined with acriflavine, are the antibiotics that will produce the best results.

Furan2 is a good combo medication that consist of two nitrofuran antibiotics (nitrofurazone and furazolidone) plus good old methylene blue. That gives it both bacteriostatic and bactericidal properties, and makes it active against various gram-negative and gram-positive bacteria. The methylene blue stains the water in the treatment tank as and prevents the photosensitive nitrofuran antibiotics from being deactivated by light. Methylene blue is effective in preventing fungal growth, and it has antiprotozoal and antibacterial properties as well, by virtue of its ability to bind with cytoplasmic structures within the cell and interfere with oxidation-reduction processes. This makes the combination of methylene blue, nitrofurazone and furazolidone very broad spectrum and quite potent.

Best of all, Furan2 can be safely combined with Aquarium Pharmaceuticals antiparasitic medications such as acriflavine to increase its effectiveness and guard against secondary infections.

Thus, when combined with an effective antiparasitic medication, a good combination drug like Furan2 can be the ultimate weapon in your medicine cabinet. It is effective against a wide range of diseases, making it a versatile shotgun for restoring order when trouble breaks out in your tank. When you suspect an infection is at work, but don’t know whether you’re dealing with fungus, bacteria, protozoan parasites or a mixed infection, Furan2 + Aquarium Pharmaceutical acriflavine is an effective combination that produces good results! Furan2 is especially effective for treating mild skin infections.

However, Heather, you have to take special precautions when administering nitrofuran antibiotics such as this because they are photosensitive and can be deactivated by light. That means you’ll need to darken the hospital tank while you treat the seahorse. Do not use a light on your hospital tank, and keep an opaque lid or cover on the aquarium during the treatments. Remove this cover from the aquarium only long enough to feed your seahorse.

You should also be aware that Furan2 will cause discoloration of the aquarium water, turning it a shade of blue-green. This is harmless and can be removed after the treatments using activated carbon filtration.

If you cannot obtain Furan2 and acriflavine either, then Neo3, a concentrated formulation of neomycin sulfate combined with sulfa compounds, is another good option for treating infection such as this. Neo3 is usually available online from either of the following vendors:

Click here:

Neo3 is sometimes difficult to obtain, and if that proves to be the case now, kanamycin sulfate or neomycin sulfate combined with triple sulfa is a suitable substitute. Kanamycin and/or neomycin sulfate can safely be combined with various sulfa compounds. One that seems to work particularly well is combining neomycin sulfate with triple sulfa. Combining both the kanamycin sulfate and neomycin sulfate with triple sulfa would be even better. You may be able to get neomycin sulfate and triple sulfa compound at a well-stocked LFS. If not, you can obtain both neomycin sulfate powder and kanamycin sulfate powder as well as triple sulfa powder from National Aquarium Pharmaceuticals. You can order them online at the following site:


This is a potent broad-spectrum, gram+/gram- aminogylcoside 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 (as well as metronidazole) to further increase its efficacy. Like other gram-negative antibiotics, it will destroy your biofiltration and should be used in a hospital tank only.

neomycin sulfate

Neomycin is a very potent gram-negative aminoglycoside 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, nifurpirinol or sulfa compounds 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.

You may also be able to find medications containing these antibiotics as their active ingredient from a well stocked fish store. A medication whose primary ingredient is neomycin sulfate or kanamycin sulfate combined with triple sulfa works well for home hobbyists and can often be obtained from the LFS

One simple way to drop the water temp in your hospital tank to position one or more small fans so they blows across the surface of the water continually (Giwojna, Oct. 2003). This will lower the water temperature a several degrees via evaporative cooling (just be sure to top off the tank regularly to replace the water lost to evaporation). Leaving the cover/hood and light off on your seahorse tank in conjunction with evaporative cooling can make a surprising difference, and just lowering the water temperature a few degrees can help a lot when controlling protozoan parasites or bacterial infections.

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, depending on how well your water temp responds to the other measures.

As long as the affected seahorse will eat, target feed it with Vibrance-enriched frozen Mysis to keep its strength up. The Vibrance includes beta-glucan as an active ingredient, and the beta-glucan is a potent immunostimulant that will boost the immune systems and help the seahorse fight off disease.

Formalin baths used in conjunction with these antibiotics will help eliminate any ectoparasites or secondary fungal infections that may be involved. Formalin is basically a 37% solution of formaldehyde and water. It is a potent external fungicide, external protozoacide, and antiparasitic, and seahorse keepers commonly use formalin to cleanse new arrivals of ectoparasites during quarantine. Formalin (HCHO) is thus an effective medication for eradicating external parasites, treating fungal lesions, and reducing the swelling from such infections. As such, formalin baths combined with the antibiotics recommended above can be highly effective in treating White Patch Disease when treatment is begun during the early stages.

Many commercial formalin products are readily available to hobbyists, such as Kordon’s Formalin 3, Formalin-F sold by Natchez Animal Supply, and Paracide-F, sold by Argent Chemical Laboratories. Or whatever brand of formalin is available at your fish store should work fine, Heather.

A formalin bath simply involves immersing the seahorse in a container of saltwater which contains the proper dosage of formalin for a period of 30-60 minutes before transferring it to your hospital tank. Include a hitching post of some sort in the container and follow these instructions: place the fish in a three-gallon bucket or a similar clean, inert container containing precisely one gallon of siphoned, aerated tank water. Medicate the bucket of water with the appropriate amount of formalin for a concentrated bath according to the directions on the label. Place an airstone in the bucket and leave the fish in the bath for 30-60 minutes. If at any time the fish becomes listless, exhausted or loses its balance, immediately place the fish in clean, untreated water in your hospital tank.

I want you to be aware of these precautions when administering the formalin bath:
Formalin has limited shelf life and degrades to the highly toxic substance paraformaldehyde (identified as a white precipitate on the bottom of the solution); avoid using any formalin product which has such a precipitate at the bottom of the bottle.

Formalin basically consumes oxygen so vigorous aeration must be provided during treatment.

Time the bath closely and never exceed one hour of chemical exposure at this concentration.

Observe the seahorse closely during the bath at all times, and it show signs of distress before the allotted time has elapsed, remove it from the treatment immediately.

If you can obtain Formalin 3 from Kordon at your LFS, these are the instructions you should follow for your formalin dip:

(a) To a clean, non-metallic container (i.e., a plastic bucket), add one or more gallons of fresh tap water treated with Kordon’s AmQuel . For marine fish use freshly prepared saltwater adjusted to the same specific gravity (or salinity) as in the original tank. Make sure the temperature in the container is identical to that in the aquarium
(b) Add 1 teaspoons of Formalin•3. This produces a concentration of 100 ppm. formaldehyde.
(c) Agitate the solution with an airstone and adjust for a moderately strong flow of air.
(d) Remove the fishes to be treated and deposit them in the container for a treatment period of not more than 50 minutes. Immediately after the treatment period, or if signs of distress are noted, remove the fishes to a previously prepared recovery tank. The fishes may be returned to their original tank, but the presence of the original disease-causing agents in the tank water may result in a reoccurrence of the disease condition.
(e) Observe recovering fishes. Make sure that tankmates do not molest them during recovery.
(f) Repeat treatment as needed, every week. Each treatment is very stressful to the treated fishes. Do not reuse the dip solution.

For additional information on treating fishes with Formalin 3 by Kordon, see the following web page:

Click here: KPD-54 Formalin-3

If you get another brand of formalin, just follow the instructions that it comes with for a concentrated bath or dip (not prolonged immersion or a long-term bath).

It’s very important to isolate the affected seahorse as soon as possible to make sure the infection doesn’t spread to its tankmates, Heather, even if you don’t have the medications on hand right now that you need to treat his problem.

A bare-bottomed aquarium with plenty of hitching posts will suffice for a hospital ward or Quarantine Tank (QT). Ideally, the hospital tank should have one or more foam filters for biofiltration along with a small external filter, which can easily be removed from the tank during treatment but which can hold activated carbon or polyfilter pads when it’s time to pull the meds out. It’s important for the hospital ward to include enough hitching posts so that the seahorse won’t feel vulnerable or exposed during treatment. Aquarium safe, inert plastic plants or homemade hitching posts fashioned from polypropylene rope or twine that has been unraveled and anchored at one end are excellent for a hospital tank. No aquarium reflector is necessary. Ambient room light will suffice. (Bright lights can breakdown and inactivate certain medications and seahorses are more comfortable and feel more secure under relatively dim lighting.)

So just a bare tank with hitching posts is all you need for your hospital ward. No heater. No reflector. No lights. No substrate. You can even do without the sponge filters or external filter in your case, just adding a couple of airstones to provide surface agitation and oxygenation. That’s it.

In a pinch, a clean 5-gallon plastic bucket (new and unused, NOT an old scrub bucket!) can serve as a makeshift hospital tank. It should be aerated and equipped with hitching posts and perhaps a heater, but nothing else. This makes a useful substitute when the Quarantine Tank is occupied or in use and a seahorse needs treatment.

Stay on top of water quality in the hospital tank/bucket with water changes as often as needed during treatment, and and when you are treating the occupants for a health problem, re-dose with the medication(s) according to directions after each water change.

All of your water quality parameters are just fine, Heather, so you don’t need to adjust to any of the readings in your main tank.

In short, isolate the affected seahorse ASAP, treat it with antibiotics, and administer a series of three formalin baths over the space of one week. (In stubborn cases, the formalin baths may need to be administered daily.) Gradually reduce the water temp in the treatment tank and keep the seahorse eating foods enriched with beta glucan such as Vibrance to strengthen their immune system, if possible.

Best of luck treating this problem and restoring your female to good health, Heather!

Pete Giwojna, Ocean Rider Tech Support

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