I am very sorry to hear about the problem your Tigertail has developed. The affected seahorse should be isolated to prevent the infection from spreading to the rest of your ponies and treated in a hospital tank with a good broad-spectrum antibiotic. The antibiotic I would recommend without being able to examine the affected seahorse is kanamycin sulfate, a potent aminoglycoside antibiotic that works very well in saltwater, as explained below:
USE: It is used to treat many sensitive gram–negative and some gram–positive bacteria. Works especially well in saltwater aquariums. Works well combined with Nitrofurazone for flexibacter (columnaris) (Symptoms: Fuzzy, thin, white coating on the body and fins. Looks like a fungus). Also useful for Pseudomonas-Open red sores or ulcerations; fin and tail damage, fins and tail are eaten away, in severe cases, down to the body. Kanamycin is very effective in high pH applications, especially Vibrio, making it useful for brackish and marine treatments.
Kanamycin can be effective for whirling disease , suspected kidney disease and dropsy.
Kanamycin sulfate appears to prevent bacteria from making their cell walls, so the cells die.
If the infected spine has an underlying abscess, then administering the antibiotics orally so that they can attack the infection internally. Therefore, as long as your Tigertail seahorse is still eating well, I would recommend treating it with some good broad-spectrum antibiotics that can be mixed with it frozen Mysis.
For this purpose, I recommend that you obtain some Seachem KanaPlex and administer it to the seahorses orally by mixing Seachem Focus and the KanaPlex together with frozen Mysis that you have carefully thawed and prepared. The Focus will bind with the medication in the KanaPlex and then bind to the frozen Mysis in a manner that masks the unpleasant taste of the medication and makes it more palatable to the seahorse. The active ingredient in the KanaPlex is kanamycin sulfate, a potent aminoglycoside antibiotic, so when the seahorses subsequently eat the frozen Mysis, they will ingest the antibiotics and get the maximum benefit they can provide.
Likewise, the Seachem Focus includes a nitrofuran antibiotic, which can be safely combined with the aminoglycoside antibiotic in the KanaPlex (i.e., kanamycin sulfate) to create a potent, synergistic combination of antibiotics that is more effective than either antibiotic used alone.
I think that will give me your best chance for a positive outcome to this problem.
Here is some additional information about the Seachem KanaPlex and how to use it properly:
KanaPlex by SeaChem
KanaPlex™ is a blended kanamycin based medication that safely and effectively treats several fungal, and bacterial fish diseases (dropsy, popeye, fin/tail rot, septicemica). Because it is absorbed by fish it is useful in treating internal infections in those situations where food is refused.To enhance palatability use with Garlic Guard™. Food may be refrozen.
Types of Infections Treated
DIRECTIONS: Use 1 level spoonful (180 mg) for every 20 L (5 gallons). Repeat every 2 days as required up to a maximum of 3 doses. Turn off UV, ozone, and chemical filtration.
To feed, blend 1 measure with about 1 tablespoon of frozen food paste. Food may be refrozen.
Contains kanamycin sulfate
Active ingredients: kanamycin sulfate (50%). Inactive ingredients: potassium sulfate (50%)
And here is some additional information on the Focus by Seachem Laboratories, which explains how to use it to combine medication with food:
Seachem Laboratories Focus – 5 Grams Information
Focus ™ is an antibacterial polymer for internal infections of fish. It may be used alone or mixed with other medications to make them palatable to fish and greatly reduce the loss of medications to the water through diffusion. It can deliver any medication internally by binding the medication to its polymer structure. The advantage is that the fish can be medicated without conDaniellenating the entire aquarium with medication. Fish find Focus™ appetizing and it may be fed to fish directly or mixed with frozen foods. Focus™ contains nitrofurantoin for internal bacterial infections. Marine and freshwater use. 5 gram container.
Types of Infections Treated:
DIRECTIONS: Use alone or in combination with medication of your choice in a 5:1 ratio by volume. Feed directly or blend with fresh or frozen food. Feed as usual, but no more than fish will consume. Use at every feeding for at least five days or until symptoms clear up.
Contains polymer bound nitrofurantoin.
Active ingredient: polymer bound nitrofurantoin (0.1%). This product is not a feed and
should not be fed directly. It’s intended application is to assist in finding medications to fish food.
And here is an excerpt from an e-mail from another home hobbyist (Ann Marie Spinella) that explains how she uses the KanaPlex together with the Focus for treating her seahorses, Danielle:
“When I bought the KanaPlex yesterday I also picked up a tube of Focus. According to the instructions, it says it makes the medication more palatable to fish & reduces the loss of the medication once it’s in the water.
So I followed the dosing instructions exactly. I used regular frozen mysis instead of PE. I figured it was softer & smaller. I was thinking along the lines of more surface area for the medication to adhere to & with the softer shell hopefully it would absorb into the shrimp a little better.
I used 8 cubes which came to just about 1 tablespoon. I thawed & rinsed the shrimp thoroughly in a little colander & let it sit on a paper towel to remove as much water as possible.
Then I put in it in a small dish & added the Focus & KanaPlex in the recommended ratio which is 5:1 (5 scoops Focus / 1 scoop KanaPlex). I mixed it thoroughly & added a few drops of Garlic Power.
Then I measured out 5 – 1/4 tsp. servings & 4 servings I placed on a sheet of Glad Press & Seal, sealed them & put them in the freezer, since it says in the instructions that you can freeze what you don’t use right away, & the remaining 1/4 tsp. I split in half & fed to them this morning. The rest I’ll give to them this afternoon & I’ll do this every day with the remaining shrimp that I already prepared & froze.
In the video you can see that the seahorses are eating it. Yea!!
Thanks for all of your help & I’ll keep you posted.”
Okay, that’s the rundown on using the KanaPlex together with the Focus so that you could administer the medication in the KanaPlex orally after adding it to the frozen Mysis for the seahorses daily meals.
Pete Giwojna, Ocean Rider Tech Support