You can usually find copper pipes already bent into nearly a circle at the hardware store. My idea would be to use one of them since you can then use premade fittings to attach a hose.
Instead of making a perfect ring out of copper, you could always make a nearly closed ring with one side attached to the hose and the other side just blocked off. I think that’d be easier.
Then drill holes for bubbles into the copper ring tube.
Or maybe see if there’s like a giant airstone they use for aquariums.
It always blows my mind that we’re such a car centric hellhole but when I was in college living in an apartment I’d have to sneak to work on my car because there wasn’t any DIY garages and it was against lease terms to work on cars on the property.
I’d have to wait until 5/6 at night right before it got dark and rush to change my oil or brakes before it got too dark to see.
These days I give my younger coworkers the pin and 24/7 access to my garages if they want to work on their cars or any projects really.
I think you’d definitely want to use some type of elastic-y epoxy to keep the ring in place. I think people would naturally kick it and prod it with their feet without realizing they’re doing it.
Yeah, I was going to recommend like a pond air ring diffuser, but you’d definitely feel like a fish in a bait bucket. Maybe you could make your own with fewer holes since there’s a lot of DIY YouTube guides on how to make those.
The idea is pretty simple since it’s just a hose fitted to a barb tee connector