The other day I went exploring and found a coral reef. I cleared it out with my silk touch pickaxe, made a sand pillar in the water to stand on so I could save my game. While I was mining coral I came back up to stand on the pillar and there was a gray animated block (like a shower) on the surface water blocks facing me like an item. It was about half the size of a block. It didnt bob like an item. I cleared some inventory space for coral and I picked it up like an item. While in inventory it was animated and it said water, nature. I tried to recreate it repeating everything I did but failed to do so. Also while I was coming back up from underwater I got stuck on something while there was nothing there, almost drowned. Might be the misplaced water block? Got back at the base and put it in an item frame, while in there it was full block sized but not animated. I was wondering what would happen so I placed it and it turned into regular water. Everything happened in my survival world without cheats.