Floating female

Dear Carol:

Thanks for the update. It sounds like your new female’s problem with positive buoyancy is already improving and I believe she will be able to resorb the excess gas from their swim bladder and restore herself to neutral buoyancy again by herself without the need for any further intervention.

It makes perfect sense that if your LFS is maintaining their aquarium at hyposalinity to minimize problems with protozoan parasites that your new seahorses might have positive buoyancy problems after being transferred to your aquarium at normal salinity, Carol. Because of the reduced buoyancy at reduced salinity at the LFS, the ponies would have to inflate their swim bladders with additional gas in order to maintain neutral buoyancy, and this would make them a little too buoyant when acclimated to it aquarium with normal salinity again. They can readjust the amount of gas in their swim bladders by gradually re-absorbing some of it through the heavily vascularized oval, but that’s a gradual process that can take several days to accomplish. Judging from your description, Carol, your new female is already making progress in that regard, so I would just be patient a little longer and see if her buoyancy problems continue to improve on their own until she is back to normal.

If you reduce the salinity in your seahorse tank slightly, that will also help her to return to neutral buoyancy, Carol, so you might want to consider gradually reducing your specific gravity to around 1.020 rather than 1.025. All of the fish and invertebrates in the aquarium should do well at a slightly reduced specific gravity of 1.020 indefinitely, and it will grow five your new female with a little additional relief.

But if your veterinarian is willing to prescribe the acetazolamide (brand name Diamox) for you, by all means go ahead and obtain the Diamox right now. That’s a very useful medication for all seahorse keepers to keep on hand in case of problems with gas bubble disease, and it can be difficult to get once a problem crops up if you don’t already have it available.

Here are the instructions for administering the Diamox, Carol:

acetazolmide/Diamox can be administered either as a series of intramuscular injections, orally via feeder shrimp bioencapsulated with the medication, in the form of a pouch flush (in the case of males), or as baths (prolonged immersion) in your hospital tank.

I will discuss all of these methods for administering the Diamox below, Carol.

The suggested treatment regimen for acetazolmide injections is as follows:

Inject acetazolamide at a dosage of 2-3 mg/kg intradermally or
intramuscularly every five to seven days for up to three treatments.
For best results, add ceftazidime (Fortaz) injections to the
treatment regimen at a dosage of 22 mg/kg intramuscularly every 5-7
days, again for up to three treatments. (Ceftazidime is an antibiotic). If these drugs prove hard to
find, the acetazolamide injections alone appear to be nearly as
effective as the combination treatment.

In order to determine the proper dosage for the intramuscular injections, you need to be able to weigh the seahorses accurately, and you must obtain the injectable form of the medications (it is not feasible to prepare a solution of the medication using Diamox tablets).

Due to their bony exoskeleton, injections are particularly challenging with seahorses. Seahorses store their limited fat reserves primarily in their tail, which is the most muscular part of their body. The meaty part at the base of the tail is best suited for IM injections. If you attempt the intramuscular injections, I would suggest targeting the base of the tail just beneath the pouch using a ventral approach with a shallow angle of attack. The needle should be directed between the scutes/plate margins for ease of penetration through the skin. The external area can be rinsed with sterile saline or a drop of a triple antibiotic ophthalmic solution applied prior to needle penetration.

Acetazolamide can also be administered orally by injecting a solution
made from Diamox (the tablet form of acetazolamide) into feeder
shrimp or the tablets can be used to administer acetazolamide as a
series of baths, as explained below:

Acetazolamide Baths (prolonged immersion)

The recommended dosage is 250 mg of acetazolamide per 10 gallons with a 100% water change daily, after which the treatment tank is retreated with the acetazolamide at the dosage indicated above (Dr. Martin Belli, pers. com.). Continue these daily treatments and water changes for 3-5 days (up to 7-10 days in stubborn cases — Dr. Martin Belli, pers. com.).

The acetazolamide baths should be administered in a hospital ward or quarantine tank. Acetazolamide does not appear to adversely affect biofiltration or invertebrates, but it should not be used in the main tank because it could be harmful to inhibit the enzymatic activity of healthy seahorses.

Using the tablet form of acetazolamide (250 mg), crush the required amount to a very fine powder and dissolve it thoroughly in a cup or two of saltwater. There will usually be a slight residue that will not dissolve in saltwater at the normal alkaline pH (8.0-8.4) of seawater (Warland, 2002). That’s perfectly normal. Just add the solution to your hospital tank, minus the residue, of course, at the recommended dosage:

Place the affected seahorse in the treatment tank as soon as first dose of medication has been added. After 24 hours, perform a 100% water change in the hospital tank using premixed water that you’ve carefully aerated and adjusted to be same temperature, pH and salinity. Add a second dose of newly mixed acetazolamide at the same dosage and reintroduce the ailing seahorse to the treatment tank. After a further 24 hours, do another 100% water change and repeat the entire procedure until a total of up to 7-10 treatments have been given. About 24 hours after the final dose of acetazolamide has been added to the newly changed saltwater, the medication will have lost its effectiveness and the patient can be returned directly to the main seahorse tank to speed its recovery along.

One of the side affects of acetazolamide baths is loss of appetite. Try to keep the affected seahorse eating by plying it with its favorite live foods during and after treatment, until it has fully recovered.

The seahorse usually show improvement of the tail bubbles within three days. Dr. Martin Belli reports they nearly 100% success rate when this treatment regimen is followed for 7-10 days, and most cases clear up in less than a week. For best results, the Diamox should be used in conjunction with a good broad-spectrum antibiotic to help prevent secondary infections. A good aminoglycoside antibiotic such as kanamycin or neomycin would work well for this.

If you prefer, you can also administer the acetazolamide orally, providing your stallion is still eating, which will allow you to treat the affected seahorse in the main tank amidst familiar surroundings and in the company of its tankmates where it is the most comfortable. You get the acetazolamide into the food by preparing a solution of the medication, as described below, and then injecting it into live feeder shrimp or even the large Piscine Energetics frozen Mysis relicta. The medication is deactivated fairly quickly once you prepare the solution for injecting, so you must prepare a new acetazolamide solution each day during the treatment period. Here’s how to proceed:

Administering Acetazolamide Orally

I have found that acetazolamide is often more effective when it’s ingested and administering the medication orally allows you to treat the seahorse in the main tank where he’s most comfortable and relaxed.

If you can obtain a small syringe with a fine needle, the acetazolamide solution can simply be injected into feeder shrimp or even frozen Mysis. Mic Payne (Seahorse Sanctuary) used this method of administering acetazolamide successfully when he had recurring problems with GBD due to maintaining a population of Hippocampus subelongatus in shallow tanks only 16-inches (40 cm) deep:

"Seahorses maintained in this system are susceptible to gas bubble disease. Specimens with bubbles around the eyes or under the epidermis of the tail are readily treated with acetazolamide (Diamox tablets 250 mg). Mix a very small amount of crushed tablet with water and inject it into several glass shrimp that are then frozen. These are then fed to the target animal at the rate of two per day for four days. Bubbles disappear on the second day."

Hawaiian volcano shrimp or red feeder shrimp (Halocaridina rubra) work great for this. If a fine enough needle is used, they will survive a short while after being injected — long enough for their twitching and leg movements to attract the interest of the seahorse and trigger a feeding response.

Leslie Leddo reports that a 1/2 cc insulin syringe with a 26-gauge needle was ideal for injecting frozen Mysis or live red feeder shrimp. They plump up when injected and ~1/2 cc is about the most of the solution they can hold. There bodies will actually swell slightly as they are slowly injected and excess solution may start to leak out. The 26-gauge needle is fine enough that it does not kill the feeder shrimp outright; they survive long enough for the kicking of their legs and twitching to assure that they will be eaten.

Administering the Diamox orally in this way is the least stressful way to medicate the seahorse, so you may want to consider trying that first before you resort to the IM injections or Diamox baths or pouch flushes.

Finally, for future reference, here are the instructions for administering Diamox as a pouch flush, which is most effective when treating chronic pouch emphysema:

Diamox Pouch Flush Instructions

ACETAZOLAMIDE (pouch flush) Dosage and Preparation Instructions
Active Ingredient: Acetazolamide
Indication: persistent and recurring pouch emphysema
Brand Name: Diamox
Dose at 0.5mL of a 62.5mg/cup solution
Supplies: narrow gauge irrigating cannula or narrow gauge IV catheter sleeve, 0.5 or 1mL syringe without needle

• Mix 62.5mg of Diamox (1/4 of a 250mg tablet) with 1 cup (approx. 237mL) of marine water with specific gravity, pH, and temperture matching that of the aquarium.
• Let the mixture settle.
• Fill the syringe with about 0.5mL of the solution, avoiding the residue that has settled to the bottom of the container.
• Hold the seahorse according to the procedure for pouch evacuations. Insert the catheter sleeve slowly and gently a small way into the pouch opening.
• Inject the solution slowly into the seahorse’s pouch. Leave the solution in the pouch.

Best of luck getting your new female back to normal again, Carol. It sounds like you’re already on the right track and I suspect that she will be able to adjust the amount of gas in her swim bladder in order to achieve neutral buoyancy again on her own over the next few days.

Respectfully,
Pete Giwojna