I’m very sorry to hear that you lost your stallion after all of your heroic efforts to save him. All my condolences on your loss, Lynn!
The prognosis is always pretty grim when a seahorse develops internal gas bubble syndrome. It is the most dangerous form of this affliction because any of the internal organs in the abdomen can be affected by the gas emboli that form in the seahorse’s blood and tissue, yet there are no outward indications of trouble at first, making it difficult to detect the problem until the condition is well advanced and serious damage has been done. The gas emboli occlude vessels and capillaries, thus restricting the blood flow to the affected area, which is what makes the internal form of GBS so insidious — irreversible damage can be done to vital organs or organ systems before sufficient excess gas builds up within the coelomic cavity to cause positive buoyancy and alert their keeper to the problem. So the odds were certainly stacked against him, Lynn, and you did everything possible to prolong his life.
If it’s any consolation, the next time you have any problems with GBS, you will already have the Diamox on hand and be ready to treat it immediately and nip the problem in the bud. In the meantime, the best thing you can do is to implement the measures we discussed in my previous post for preventing gas supersaturation and minimizing problems with GBS to help assure that none of your other seahorses will be affected.
First of all, whenever you find yourself dealing with an environmental disease such as GBS, a water change is an excellent place to start. At the first sign of GBS, I suggest you combine a 25%-50% water change with a thorough aquarium clean up (Giwojna, Jan. 2004).
Secondly, consider adding an ordinary airstone to your tank, anchored just beneath the surface of the water. That will add surface agitation, extra aeration, and better gas exchange at the air/water interface (Giwojna, Jan. 2004). Unless you’re quite certain your system already has plenty of water movement, it is also advisable to add a small powerhead for extra circulation (Giwojna, Jan. 2004). Seahorses can handle more water movement than most folks realize, and you can always turn it off during feedings. Just screen off the intake for the powerhead as a precaution so it can’t accidentally suck up a curious seahorse (Giwojna, Jan. 2004).
Thirdly, I recommend that home hobbyists who have had a problem with GBS in the past reduce the salinity in their seahorse tanks to at least 1.020 in order to increase the amount of dissolved gases the water can hold before it become saturated. Reducing the specific gravity to 1.015-1.017 is even better in most cases, providing you aren’t keeping live corals or delicate invertebrates in your seahorse tank. Likewise, reduce the water temperature in tanks with a history of GBS to around 68°F-72°F in order to increase the amount of dissolved gases the water can hold before it become saturated. Both these simple measures will help prevent gas supersaturation and reduce future problems with GBS accordingly.
Finally, use shorter hitching posts and holdfasts that will confine your seahorses to the bottom half of the aquarium and reduce the water temperature. Shorter hitching posts will get the maximum benefit from whatever depth your tank can provide, and lowering the water temperature and specific gravity allows the water to hold more dissolved gases, which can help avoid any tendency toward supersaturation (Cozzi-Schmarr, 2003).
Those simple measures may make a big difference. Just maintain good water quality, provide your seahorses with the stress-free environment, add a shallow airstone and perhaps an extra power head to provide better water movement and gas exchange, remove your protein skimmer as a precaution, keep things cool and reduce the water temperature and specific gravity of your seahorse tank, and you can reduce your risk of GBS considerably. Hopefully, that will assure that you never have a need for the Diamox and you never have to deal with this type of problem again, Lynn.
Best wishes with all your fishes!