Redox potential is important but at the end of the day ozone seems more useful for large systems, 1000g+, than smaller ones. Basically no altitude has zero effect on ozone. All it is is a 3 oxygen molecule that is highly unstable and due to the strong desire to bind immediately with anything it can it breaks off of the O3 and the O-² is then going to try and rip apart any molecule it can to form the necessary bonds to fill its outer L shell up with a total of 6 electrons because two are still missing.
The oxidizing power of ozone is about twice that of chlorine. It strips cilia from small organisms and eventually kills them, and once it enters can do lethal damage. It works by oxidizing those dissolved organics, as I explained in more layman's terms above, along with managing bacteria populations and breaking up small particles like detritus... When it does this, it's taking those complex mineralized organics and making them into more active compounds in the water column that are removable via skimming. This is sort of a compounding effect because whenever you introduce ozone to a system with a skimmer, and you add the air from the skimmer with ozone, the result is also a more stable foam.
Downsides include reacting with bromide, chloride, forming hypo-bromite, hypo-chlorite. These are also oxidants and extends the power of the ozone into potentially hurting fish and gill tissue, larvae, and other micro organisms that would otherwise be a little more protected against just ozone.
Ozone will also react with calcium in your water, can kill macro algae at high levels, and can oxidize medications or chemical additives, meaning their effects may (and will) potentially change as well. So if you have ozone, you have to turn it off if you ever intend to treat the system with medications.
On top of all this, it's not good for us (humans) when it's smellable in the room itself, and it destroys things like rubber and certain plastics in a hurry. This shortens the use life of your skimmers, for example, depending on the plastic they are made from, and is something to be aware of. Some people pass the ozone through a carbon filter, or running the ozone air from the skimmer back through wet carbon, to prevent some of these drawbacks, but I've never ran ozone myself to speak to this. You however can't run dry ozonated air through a dry activated carbon bag like the people who put them on top of their skimmers however because it can spark a fire. In the beginning of reefing, ozone was a big deal.
This all said, generally speaking the less nuclear option with some of the same benefits rests within UV sterilizers as they naturally generate some amount of ozone. Adding a UV sterilizer will marginally improve how much you can remove with protein skimming.
UV is a different subject entirely but I suspect the vast majority of people running UV are not replacing their bulbs often enough for the argument against UV to have any meaningful difference on their tanks. UV bulbs typically have a 5000 hour lifespan and after that, the bulb is useless. Some bulbs made today might be more effective, but be aware that regardless of manufacturer direction, this is the reality of using UV is every 6 months you'll need a new bulb even if it's a low pressure high intensity bulb.
Then there's the issue of energy production. Bigger ones work better because there's more time to bombard your water. Some things are destroyed around 35k uw sec cm² and some like cryptocaryon aren't destroyed until over 100k uw sec cm², and lower low= better kill rate, especially if the bulb is older. This is because UV bulbs have higher efficiency at higher operating temperatures and the difference is as much as 50% loss in efficiency operating at 72° as opposed to say 106° of the bulb itself. You can always measure your flow rate by testing the sterilizer in a bucket at similar head pressure to your tank, and then measuring the amount of water and doing the conversion from liters or gallons to gallons per hour, or if you're lazy, allow it to fill between two 5g buckets, time it, and then calculate:
(60 minutes/minutes to fill) X 5gph =flow gph
To walk back to part of your original question, oxy redox potential is always going to help a tank at higher levels, -- to a certaine extent. You don't want over 400 millivolts. 200-360 is probably fine. That said, generally redox potential goes down as pH and temperature rise, but most people run skimmers or other ways to incorporate oxygen into their tanks to raise it. Mike Paletta wrote an article for Seascope in 1988 about his experiences, which I'll attach, though due to its age if you have any further questions it might be worth reaching out and digging around for some of his more recent articles about it, if any.
https://www.instantocean.com/Ocean-of-Knowledge/SeaScope/SeaScope-Index-by-Subject.aspx
I know this is a lot of information, but I want you to have something you can refer back to in a meaningful way. Ozone does have an impact on smaller systems and can improve virtually any system, but the poison is in the dose and ultimately the smaller tanks that balance is harder to strike, whatever it may be.