There is a problem when you place water from a bucket onto a block that already has water on it. it does not matter if it is a source or it is active. When this happens it acts as if you are placing a block down and the particles show as if you broke the block.

• In the first picture I placed a bucket of water on flowing water.
• In the second picture I placed a bucket of water on a source block of water.

Hope this gets fixed!!