Hey Rooster Gold,
Since the world is built on a voxel system where each block 1 meter block occupies a full 1 meter space, regardless of its visible shape (in most cases), the water will not remain within the hollowed sink area. Instead, it will flow over the shape and outward. This is normal behavior. If any of the spaces next to that 1-meter space are open, the water will continue to spread to those areas.
To allow it to fill that space, you will need to place a plate block with the "empty space" facing out towards you, fill the sink space with water, and then place a sink top on it. This setup will properly contain the water.
If you run into anything else or would like us to take a closer look, it really helps to include:
- An in-game screenshot using F11 to show the POI name and coordinates
- The output log from your game session
- Step-by-step details on how to reproduce the issue
These details make it much easier for us to track things down and get them fixed later. They're especially important when investigating POI's and in-game decoration, since the seed name controls things like world generation, terrain, biomes, world deco placement, and POI locations. Having that information helps us to recreate what you're seeing.
Please let me know if I misunderstood what your goal was with the sink and water placement so I can take another look and help further.
Best,
Dollie