Bought a house two years ago and I'm trying to learn everything I can about the pool that came with it. It is a 10,000 gallon in-ground pool built by Blue Haven. I've attached some pictures of my equipment and want to better understand a few things. First, what is the canister to the left of the filter with the busted pressure gauge? I plan on replacing gauge asap. I'm now worried about it because it has some green algae at the bottom. Second, after reading online, I understand that I have an ozonator attached to the house. I've never done any maintenance on this and know little about it other than I need to replace bulbs inside. I don't see any glow inside and doubt it's working as it should based on the previous homeowners maintenance practices on other parts of the house. Third, do Jandy valves tend to leak/need replacing every few years? Mine started leaking and is right above the pump which is leading to some rust. My last question is one of my returns is totally dead and was barely working last year. I think it's underground plumbing that's leaking but wanted to ask. My returns blow huge bubbles every time I turn on the pump no matter how long it has been. Thanks in advance for your help!