I'm looking for a short clip I saw on Twitter between 2017 and 2020. I think it was uploaded by a Japanese CG artist, and featured a photorealistic human head floating in a fish tank.
The head was slightly deflated, like someone had removed the skull, but the water was giving it shape again. It looked kinda like how a plastic bag might inflate underwater, or the bulbous section of a jellyfish. I'm fairly certain it was supposed to invoke a jellyfish because there were wires or tendrils protruding from where the neck should begin.
There was a second creature slightly out of focus towards the rear of the tank, sitting on the bottom. It had a fish-like tail and the texture of human skin. Its head was off-camera. The tank itself was empty aside from the two creatures, and seemed to be against a grey wall. It looked like it might be some kind of laboratory environment.
The closest thing I can compare it to is this video, but with no commentary and less shaky cam. The video was just a short loop of the head floating there, and the second creature in the back did not move.
It's also got nothing to do with the Seaman game series. I can understand the similarities but this was a far more realistic style of CG, and I'm pretty sure the artist had lots of other body horror works on their account.