My Seahorse is Floating, but Still Eating Well?

Hi! I am in desperate need of some advice for my presumably sick seahorse :(. I am pretty new to seahorse keeping, and I started taking care of my first pair of seahorses in January of this year. One of my seahorses, the male, just recently began swimming odd and floating. Despite this odd behavior for the past few days, he is still eating normally. I feed him twice a day, and he has even still been just as receptive to his mysis- still being very excited to eat it and poking his head by me when he sees his food. Other than his odd swimming pattern, he doesn’t appear to behave any more odd than usual. However, I still know something is wrong, but I’m not sure what condition I should try to treat.

I can’t tell if his brood pouch is inflated because I haven’t dealt with this issue before and I don’t have anything to reference. It doesn’t appear too different from normal though. I’m hesitant about performing a pouch evacuation (I have never done one before) until I’m certain he might have gas’s trapped in his pouch, but since I still want to act as soon as possible would it be harmful if I performed one and there wasn’t any gas trapped? I would probably use the basic method of holding him and trying to gently push out the gas with my thumb and index finger since I am nervous to attempt it with a needle in the side of his pouch. I also don’t want to cause him any unnecessary stress, since he is still eating normally, but I also want him to be relieved of this issue if it is a problem to his health.

One of the potential issues I have also read about is an internal problem such as internal gas bubble Syndrome or an inflated swim bladder. I was wondering if there is any difference between these two issues, and if so what medications would be most effective for treating each of them? I have seen some of Peter’s responses mentioning Diamox and other various prescription antibiotics, so I was also wondering how I would access these if needed? I live in central Wisconsin and unfortunately I haven’t found any veterinarian or marine biologist remotely near me who deals with saltwater marine life or even fish in general. Therefore, Im not sure how I would get access to a prescription for these necessary antibiotics and I was wondering if there are any other ways of accessing them?

Now I will go over some background information on my seahorse in case it will help. I house my two seahorses in a 30 gallon tall tank, which I feel may be a little small even though the breeder said it would be fine (I’m just extra cautious about this stuff since I want to provide my seahorses the best care!!). The tank parameters are pretty normal. Salinity is 0.021 and sometimes fluctuates to 0.022 if I accidentally delay my daily evaporation top-off. Nitrites and ammonia are 0. Nitrites are usually around 10-20 (a bit high I know). Unfortunately, I haven’t been able to get my nitrites below these parameters even with added oxygenation and carbon buffers. I tested my plain tap water and the nitrite level was also 10 I believe. At the time of writing this, I have just performed a 75% water change because my normal water change schedule got delayed with school (I don’t want to let this happen again!). It was a few days afterwards that my seahorse started having these issues with swimming, so I’m not sure if it is related? Also, my seahorses are Hippocampus Erectus and they are both male. I initially thought they were male and female, because the pet store told me they were, but I am now certain they are both male. I did get them when they were really little so they might have just been misgendered since I’ve read it’s difficult to sex baby hippocampus erectus (I’m not sure if this is true though).

I would really really appreciate some advice on this issue! I am so worried about my sweet baby, and I since I’m new to seahorse keeping I want to make sure I am carrying out the proper treatment for him. Please let me know your thoughts- it would mean the world to me and my seahorse!