Welcome to RC!!!!
I'm in the same boat your in. I'm looking at Ozone and controller for my 75 gal.
I leaning towards the Sander ozonizer 50mg/hr with a Milwaukee controller w/probe, air drier and coralife pump to feed the ozone thru mu Euroreef skimmer (recirculating). CS6-2
There is a lot of information on Ozone and it can get pretty confusing. I considered the Red Sea with controller and probe, which is nice because its one unit. But if you have any issues with the Red Sea replacement or repair, you have to replace the whole unit. With the Sander is a separate unit and the Milwaukee probe as well. So if one fails you wont be out the extra $$$ compared to the Red Sea.
Hopefully we will have some others chime in.