There is a major bug in the underwater houses (Sunken Palace and Briny Deep Retreat) that I have noticed. The problem is that players are able to place fish over the house limit. I created a ticket for this issue with attached screenshots, but it was recommended to post on this forum. Another issue with fish placement in underwater houses is that the attic UI doesn't have a location to pick up fish remotely. It would be great if this could be an added element for quality of life!