Great points. I am getting this because of Dino’s in my 45g tank. The reason why I don’t want to run it 24/7 going forward is simple because I don’t think it’s necessary. I believe the cause of my Dino’s is that I moved everything out of my 45g a couple months ago into my new 130g. I then used chemiclean to get rid of the cyano outbreak I had and got Dino’s after from that and also not having anything but inverts and a nem. I recently moved the tank and added a pair of clowns and didn’t notice Dino’s anymore from having a bioload. However, there was something wrong with the female clown so I moved them into QT, thus leaving the tank barren again and I noticed the reassurance of this. I’ve been ghost feeding and feeding the nems in there but I’m hopeful once I have it stocked again, I won’t have any issues.
Because of the above, I don’t believe 24/7 UV is necessary. Further, I was also more thinking of getting one piece of equipment that I could use between the two tanks on an as needed basis.