Played the game, actually completed it.
The game is fun, and it works fine. The pond area, the dungeons, the Inventory. Quite a lot of stuff is in there. I thought that at some point I will have to adjust my items to fight special enemies (very quick, oxygen draining, very tough but slow), but it was not the case. For example, in the beginning, I was really afraid of octopus, because the sea horse said so, but he was not that tough.
In general, the difficluty scales with levels, but so do items, so the gameplay feels a little repetitive after 3-4 dungeons. Still, the game is not very long, and it remains fun to play. Also, playing as a fish, and getting better jaws and scales is amusing. Very enjoyable.