Re:Methylene Blue question (peter?)


Pete Giwojna wrote:
[quote]Dear Joe:

Yes, sir, it is a good idea to quarantine new arrivals and screen them closely for health problems before introducing them to your main tank, and you are to be commended for doing so. However, it’s important for the quarantine tank to have an active biological filter to maintain good water quality and avoid ammonia spikes during the 4-6 week period in isolation. Otherwise, quarantining the seahorses may do more harm than good because you will be fighting a losing battle to maintain water quality and avoid dangerous ammonia spikes. I will provide you with additional information explaining how to screen seahorses to identify potential problems and how to quarantine them properly later in this e-mail, Joe, but first I will address your question regarding the methylene blue.

I do not recommend treating all new arrivals with methylene blue prophylactically. Rather, it is appropriate to treat seahorses that have developed symptoms of ammonia poisoning following long-distance shipping with methylene blue, Joe. In most cases, a very brief 10-second dip in concentrated methylene blue is all that’s needed, as discussed below in more detail. In severe cases, more prolonged treatment with the methylene blue in a hospital tank may be necessary, which is what I believe you are currently attempting. In that event, the methylene blue is less concentrated and I typically do not feed the seahorses during the three-day treatment period because eating and excreting in the hospital tank will make it difficult to keep the ammonia at zero, which is very important for the seahorses recovery. Well-fed seahorses in good condition can fast for three days with no difficulty whatsoever and the ponies suffering from ammonia poisoning that may require the long-term treatment with methylene blue typically have no appetite initially in any case…

Here is some additional information regarding ammonia poisoning and how it should be treated, Joe:

Ammonia Poisoning & Nitrite Toxicity

The most obvious symptoms of ammonia poisoning and nitrite toxicity are a loss of equilibrium, hyperexcitability, increased respiration and oxygen uptake, and increased heart rate. At extreme ammonia/nitrite levels, fish may experience convulsions, coma, and death. Seahorses exposed to less extreme ammonia/nitrite levels will struggle to breathe. They will be lethargic and exhibit rapid respiration. They may appear disoriented, periodically detaching from their hitching posts only to sink to the bottom.

Ammonia poisoning and nitrite toxicity are completely reversible providing the seahorses weren’t exposed to toxic levels for too long, and the best first aid you can provide for ammonia/nitrite poisoning is to immediately transfer the seahorses into clean, well-aerated saltwater with zero ammonia and zero nitrite.

The next thing you should do is to give the seahorses a quick 10-second dip in concentrated methylene blue to help them recover, as discussed below.

Exposure to moderate levels of ammonia and nitrite, or high levels of nitrates, can change the normal hemoglobin in the seahorse’s blood stream to a form (i.e., methhemoglobin) that is no longer able to transport oxygen. If this becomes severe enough, it will leave the affected seahorse starved for oxygen, which makes it very weak and fatigued. As a result, the affected seahorses may detach themselves from their hitching posts periodically and rest on the bottom, unable to exert themselves in their weakened condition. As you can imagine, being deprived of oxygen really wipes them out in terms of loss of energy and stamina. And it also results in respiratory distress, and rapid, labored breathing or gasping for air as they try to oxygenate themselves and compensate for the lack of normal hemoglobin.

One of the properties of methylene blue is that it can reverse this process and convert the methhemoglobin in the red blood cells back into normal hemoglobin, which can then pick up and transport oxygen again as usual. That’s why it is so helpful in relieving shipping stress and treating ammonia exposure and nitrite poisoning. For this reason, you may want to pick up some methylene blue at your local fish store and keep it on hand in case it is ever needed (the Kordon brand of methylene blue is best, in my opinion). So be prepared to give the seahorses a quick dip in methylene blue if necessary.

The usual criteria for determining whether or not methylene blue is needed to help seahorses recover from exposure to high levels of ammonia is their respiration. If the seahorse has labored breathing — huffing or rapid respiration — then methylene blue is called for. Likewise, if the seahorse is experiencing convulsions or it’s behavior otherwise indicates it is suffering from more than temporary disorientation and loss of equilibrium, such as lying prostrate on the bottom, unable to right itself again at all after two or three hours have passed, it may benefit from methylene blue to assist its recovery.

Commonly known as "meth blue" or simply "blue," methylene blue is a wonderful medication for reversing the toxic effects of ammonia and nitrite poisoning. Methylene blue transports oxygen and aids breathing. It facilitates oxygen transport, helping fish breathe more easily by converting methemoglobin to hemoglobin — the normal oxygen carrying component of fish blood, thus allowing more oxygen to be carried through the bloodstream. This makes it very useful for treating gill infections, low oxygen levels, or anytime your seahorses are breathing rapidly and experiencing respiratory distress. It is the drug of choice for treating hypoxic emergencies of any kind with your fish. However, methylene blue will destroy nitrifying bacteria so it should be used in a hospital tank or as a brief bath or dip only (if used in an established aquarium, it will impair the biological filtration and the tank may need to be cycled all over again).

Here is some more information that may be helpful when you treat the seahorses with methylene blue:

If you can obtain the Kordon brand of Methylene Blue (available at most well-stocked local fish stores), there are instructions for administering it as a very brief, concentrated dip are as follows:

For use as a dip for treatment of fungus or external parasitic protozoans and cyanide poisoning:
(a) Prepare a nonmetallic container of sufficient size to contain the fish to be treated by adding water similar to the original aquarium.
(b) Add 5 teaspoons (24.65 ml) per 3 gallons of water. This produces a concentration of 50 ppm. It is not recommended that the concentration be increased beyond 50 ppm.
(c) Place fishes to be treated in this solution for no longer than 10 seconds.
(d) Return fish to original aquarium.

When you administer such a dip, hold the seahorse in your hand throughout the procedure and time it closely so that the dip does not exceed 10 seconds.

And here are Kordon’s instructions for administering the methylene blue in a hospital tank if longer-term treatment seems appropriate to reverse more severe cases of nitrite poisoning and ammonia toxicity:

As an aid in reversal of nitrite (NO2-) or cyanide (CN-) poisoning of marine and freshwater aquarium fishes:
(a) Remove carbon filter and continue to operate with mechanical filter media throughout the treatment period.
(b) Add 1 teaspoon of 2.303% Methylene Blue per 10 gallons of water. This produces a concentration of 3 ppm. Continue the treatment for 3 to 5 days.
(c) Make a water change as noted and replace the filter carbon at the conclusion of the treatment.

See the following link for more information on treating with Kordon’s Methylene Blue:

Click here: KPD-28 Methylene Blue

If you obtained a brand of methylene blue other than Kordon, just follow the instructions the medication comes with. The dosage will vary depending on the brand of methylene blue you are using.

Okay, Joe, that’s the quick rundown on treating seahorses for ammonia poisoning. If your new seahorses were exhibiting these symptoms of ammonia poisoning or nitrite toxicity described above, then you certainly did the right thing by treating them with the methylene blue, and no harm will come from the use of the medication providing you use the proper dosage. The seahorses should not be maintained in the methylene blue for more than 3 to 5 days at the recommended dosage.

You will want to perform a water change after three days to remove as much of the ammonium blue as possible, and the seahorses can be fed as usual following the water change. If the problem was ammonia poisoning or nitrite toxicity, they should be back to normal and have a healthy appetite again. But you should not maintain them in a quarantine tank without biological filtration for an extended period because it will be very difficult to maintain good water quality and avoid ammonia spikes and stressful conditions without inactive biofilter.

Here is some additional information explaining how to screen your seahorses and quarantine them properly, sir.

Let’s begin by discussing the warning signs and symptoms to check for when you’re giving your new arrivals or a seahorse at your local fish store (LFS) a visual inspection, as outlined in the "Sygnathid Husbandry Manual for Public Aquariums, 2005 Manual":

<Open quote>
Physical Examination — Visual Assessment

When performing an initial physical exam, the posture and buoyancy of the seahorse should be closely scrutinized. A seahorse bobbing at the surface is abnormally and positively buoyant. Buoyant animals will often struggle to maneuver deeper into the water column. They should be evaluated for air entrapment problems such as air in the brood pouch (males) or hyperinflated swim bladders. If the tail is extended outward caudodorsally or ‘scorpion-style,’ examine the subcutis of the tail for gas bubbles (subcutaneous emphysema). Subcutaneous emphysema of tail segment also appears to be a condition restricted to males.

Just as abnormal is a seahorse that is lying horizontally at the tank bottom for extended time periods. This may be an indication of generalized weakness or it may indicate negative buoyancy associated with swim bladder disease or fluid accumulation in the brood pouch or the coelomic cavity.

Evaluate the seahorse’s feeding response. Seahorses normally forage almost constantly during daylight hours. An individual that consistently refuses appropriately sized live food is behaving very abnormally and should receive nutritional support to meet its caloric needs.

The rate and pattern of breathing should also be evaluated. Rapid breathing and ‘coughing’
(expulsion of water in a forceful manner through the opercular opening or the mouth) suggest gill disease [or gill parasites].

The entire body surface including the fins should be examined for hemorrhagic regions,
erosions, ulcerations, excessive body mucus, unusual spots, lumps or bumps as well as the presence of subcutaneous gas bubbles. Evaluate both eyes for evidence of periorbital edema, exophthalmia, and any testicular or corneal opacities. Since seahorses are visual predators, maintaining normal vision is absolutely essential to successful foraging. The tube snout is also very important to normal feeding activity. It is utilized like a pipette to literally suck prey out of the water column.

Evaluate the tube snout for evidence of edema, erosions, and successful protraction/retraction of the small, anterior, drawbridge-like segment of the lower jaw. Close evaluation of the tail tip for erosive/necrotic lesions should also be performed.

Finally, the anal region should be closely evaluated for redness, swelling, or tissue prolapse. For closer evaluation it may require getting the seahorse in hand. If this is the case, wear non-powdered latex gloves to prevent injury to the integument of the animal.
<Close quote>

If the seahorse passes this visual examination, and is eating well and behaving normally, with none of the red flags or warning signs discussed above, only then should you consider taking him home. That’s a quick checklist you can use to determine if the seahorses at your LFS appear to be healthy or not before you make a purchase.

The Quarantine Tank

Once you have found healthy specimens with none of the symptoms or problems outlined above and make your purchase, it is equally important to quarantine the new seahorses before you introduce them to your main tank! A potential problem when obtaining seahorses from your LFS is that they are typically maintained in aquaria that share a common filtration system with all of the other fish tanks in the store. Of course, those other fish tanks house a wide selection of wild fish that have been collected from all around the world, and any pathogens or parasites those wild fishes may have been carrying can be transmitted through the common water supply to the seahorses. That makes fish from your LFS potential disease vectors for a whole laundry list of disease organisms and makes it mandatory to quarantine such specimens before they are introduced to your display tank.

In its simplest form, quarantining aquarium fish simply involves introducing them to a quarantine tank (normally with the same aquarium parameters as the tank they will be eventually going in) all by themselves for a period of several weeks to assure that they aren’t carrying any diseases. The idea is that any health problems the wild fish have will manifest themselves in isolation during this quarantine period, and they can then be treated with the appropriate medications without affecting the health of the rest of the fishes in your display tank. While they are in quarantine, some hobbyists will also treat wild fish prophylactically for internal parasites using praziquantel or metronidazole, and for any external parasites they may possibly be carrying using formalin bath(s) and/or freshwater dips.

A bare-bottomed aquarium of at least 10 gallons (the bigger the better) will suffice for a 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, if necessary, but which can hold activated carbon or polyfilter pads when it’s time to pull the meds out. No aquarium reflector is necessary. Ambient room light will suffice. (Bright lights can breakdown and inactivate certain medications and the fish in quarantine will be more comfortable and feel more secure under relatively dim lighting.)

For seahorses, it’s important for your quarantine tank/hospital tank to include enough hitching posts so that the ponies won’t feel vulnerable or exposed during their stay in quarantine. Aquarium safe, inert plastic plants or homemade hitching posts fashioned from polypropylene rope or twine that has been unraveled and anchored at one end work well for this if you’re short on such decorations.

Cycling the sponge filters is important because otherwise the only way to maintain water quality is by making partial water changes every day or two throughout the treatment period. Breaking in the biological filtration will eliminate the need for such frequent water changes and assure that the quarantine period is less stressful for the fish by eliminating transient spikes in the ammonia and/or nitrite levels.

Be sure to avoid sponge filters with weighted bottoms or other metal components since they will rust when exposed to saltwater. Sooner or later this will cause problems in a marine aquarium. Select a sponge filter that has no metal parts and is safe for use in saltwater. The proper units will have suction cups to anchor them in place rather than a weighted bottom.

Once your quarantine tank is up and running, new arrivals from your LFS that pass the preliminary visual screening should then be treated prophylactically while they are in quarantine, as discussed below.

Shedd Aquarium Seahorse Quarantine Protocol
February 2005

The following quarantine protocol is currently employed at the John G. Shedd Aquarium where the most prevalent disease problem accounting for the highest morbidity and mortality to date is acute to subacute vibriosis. Newly acquired specimens are kept in isolated quarantine tanks for a minimum of 30 days.

(1) Live food (Artemia) soaked in DC-DHA SELCO is fed during the first week of
acclimation. This product is purported to have antimicrobial properties. This was
adopted into our protocol to prevent early colonization of the gut with Vibrio sp. of
clinical significance. DC-DHA SELCO is a product of Artemia Systems, INVE
Aquaculture NV, Hoogveld 91, 9200 Deudermonde, Belgium.

(2) A bivalent Vibrio bacterin against V. anguillarum and V. ordalii (Apha Dip 2100,
made by Syndel International Inc., Vancouver, B.C.) is administered as a dip on day
1 and day 15 of quarantine per manufacturer’s labeled recommendations. We have
not challenged vaccinated syngnathids with pathogenic field isolates of Vibrio sp.
to assess the protectivity of this bacterin. This work should be performed and
compared with the protectivity of autogenous bacterins derived from in-house
isolates cultured from post-mortem specimens.

(3) Live Artemia is soaked in fenbendazole to achieve a concentration of 0.25% to 0.5%
of the wet weight of Artemia. This is fed out for three consecutive days (days 8,9,
and 10 of quarantine). This three-day regimen is repeated in two weeks (days 22,23,
and 24 of quarantine). This is administered to combat enteric nematodes. However,
recent studies evaluating actual concentration of drug absorbed by the Artemia may be
quite low (A. Stamper, Living Seas at EPCOT, personal communication). Further studies
are needed.

(4) Praziquantel baths are administered on day 14 and day 28 of quarantine. Praziquantel
is administered at 1-2 ppm for a minimum of 24 hours. This is done primarily to
combat enteric cestodes and trematodes since, to date, ectoparasitic monogenetic
trematodes have not been found in any syngnathid in our collection (nor are there any
published reports of monogeans in syngnathids anywhere in the fish health or
parasitology literature).

(5) A dip (10 minutes in either a low salinity bath or 45 minutes in a 200 ppm
formalin bath) is performed at the end of quarantine primarily as a final therapeutic
treatment against any putative ectoparasites. In addition, the sediment in this dip is
concentrated and examined under the dissecting microscope for the presence of any
protozoan or metazoan parasites before the fish are deemed suitable for exhibition.
<Close quote>

Marine fish and seahorses should be quarantined for 4-6 weeks as explained above. This is especially important for wild-caught seahorses and seahorses that are obtained from your local fish store rather than directly from the breeder. The only exceptions are High-Health seahorses obtained directly from Ocean Rider (, which are guaranteed to be free of specific pathogens and parasites. There is no need to quarantine high-health seahorses before they are introduced to the main tank, which simplifies things for the home hobbyist. The Ocean Rider aquaculture facility provides multi-generational captive-bred-and-raised seahorses that have now reached a high level of domestication and are very well adapted to aquarium life.

Best of luck with your new arrivals, Joe!

Pete Giwojna[/quote]

{I just want to thank you for this information.}

It took me a long time looking up the use of methylene blue for
exposure to high nitrite and ammonia levels.
I have received fish in the mail before and they arrived
within 24 hours and were healthy I was lucky.
and with this information I will feel that I will be ready.
I just want to be prepared for my next fish arrivals.


America's Only Seahorse Aqua-Farm and One of Hawaii's Most Popular Attractions

Ocean Rider seahorse farm is a consistent Trip Advisor Certificate of Excellence Award Winner and "Top 10 Things To Do" Kona, Hawaii attraction. Our "Magical Seahorse Tours" are educational and fun for the whole family.

Tour tickets are available for Purchase On-Line. Space is limited and subject to availability.

small seahorse Ocean Rider, Inc. is an Organic Hawaiian-Based Seahorse Aqua-Farm & Aquarium that Follows Strict Good Farming Practices in Raising Seahorses and Other Aquatic Life.

Seahorse Hawaii Foundation

Inspiring ocean awareness by saving the endangered seahorse and sea dragons around the world from extinction through conservation, research, propagation, and education.

Help us save the seahorse and the coral reefs they live in with a tax deductible contribution to the Seahorse Hawaii Foundation. You will be helping to protect and propagate over 25 species of endangered seahorses, sea dragons and friends.

Make A Tax-Deductible Donation Today!

A Different Kind of Farm (Video) »

Ocean Rider Kona Hawaii

Ocean Rider Kona Hawaii
Seahorse Aqua-Farm & Tours

73-4388 Ilikai Place

Kailua Kona, Hawaii 96740

Map & Directions


Contact Ocean Rider

Copyright ©1999-2023
All Rights Reserved | Ocean Rider Inc.

My Online Order Details

Purchase Policy

Site Terms and Conditions