I opened the sim to visitors recently. Today I see on mini-map a big moving rectangular on my bay..

[Abigail Longmeadow]

Possibly a mega-prim sim surround?

[Abigail Longmeadow]

Possibly a mega-prim sim surround?

[Madelaine McMasters]

I visited your sim (you logged out just as I arrived). I think the thing moving about your bay is a school of fish, most of them blue, some orange. They seem to circle about a point that moves just like the rectangle in/near the bay on the mini map. The fish spend most of their time under the ocean floor, and not visible to you. You might want to relocate them or change their path, if possible.

I didn't stay long enough to look the entire place over, but it looks like you've been having fun!