Hey all. In the process of draining and repainting our pool. Have wondered about this mystery item for a while. Is this a covered jet? Or?? We have two other jets (one in shallow end, one in deep end) of our kidney shaped pool, and have kinda struggled with water movement efficiency... pool is 30+yrs old, and we know little about it. Thoughts? Why would this be covered? Worse case I break it open and ....?