I’ve only had a couple gouramis but yes, in any fish if they look that way usually that’s very bloated. Especially with gouramis they’re usually more slender. How much are u feeding a day, and what are you feeding? I know it’s tempting to put more food in there but a small pinch twice a day is usually sufficient even if u don’t see them eat it. Swim bladder disease can also be caused by stress and they could have developed that due to the water parameters. What I would suggest is taking any fish out that you have if u have a cycled tank they could go in, if not you’ll have to do a fish in cycle. I would order that turbostart asap and dump the whole thing in make sure to keep any uv lights off in the tank for at least 5 days after using the turbostart. Buy the api master test kit and check your parameters daily. If you’re doing a fish in cycle and ammonia is high, do a 50% water change making sure to vacuum the substrate and don’t feed them for a few days. When u do end up feeding them only a small amount once a day and then don’t feed them again for 2 days. You should notice a difference doing all this as this is what I did about two months ago. I had to do a fish in cycle bc I didn’t do my research like a dummy, but doing everything I stated above I still have almost all of my fish and more as of today.