Nice on killing the ozone box. Yes, having the UV come on should help your FC loss (less FC loss if it is off). It has sanitizing properties, but really only has benefits for an indoor pool. They are not necessary for an outdoor pool and will only consume FC, not really help with sanitizing.
Turning the pump down low does no damage. There are lots off threads and pool school article on pump run time and speed. You should be good there.
Can you unplug the UV? If so, just to ensure it doesn't go on, unplug it. If it was installed correctly, there should be a couple of bypass valves. You can stop the pump and open the bypass valves and no water will flow through the UV. Can you post a picture of your setup? Can you provide a make and model # on the UV?
Still trying to think through all the possibilities to help...

It’s paramount ultra UV 2 and clear o3 ozone system. I can unplug it but have no idea how to bypass it and wasn’t sure if water would still pass through correctly if I did unplug it. So I haven’t. Any thoughts after seeing the picture?