Here's a definitive article on UV Sterilization. Over the years it has been revised and become more complicated (The Category A,B,C has been added)
Information how a TRUE Aquarium, Pond UV Sterilizer/clarifier work. Category A, B, & C Sterilizers. Affect on green water, disease prevention, & Redox
www.americanaquariumproducts.com
This chart taken from the article is very useful:
View attachment 1407971
Not too many fish keepers attempt Level Two Sterilization but aim for Level One Sterilization. The flow rate of an FX-6 would give you a turnover rate of 1.5 in your 360 gallon tank. Keep in mind that each UV sterilizer has a recommended maximum flow rate. You will need 25-40Watts. If you read the article, the author sells UV sterilizers.
I run a 40W Lifegard Aquatics on my 300 gallon tank. Bulb, ballast and glass sleeve need changing periodically and can get expensive. The unit is also tall and probably wouldn't fit in a stand. I liked what I read about the quartz bulb. I'm going with two 120W UVs on my big tank.
Emperor Aquatics is now Pentair Aquatic Eco-Systems. Why does BRS recommend this? When it comes to UV most other companies will recommend a small UV for a large tank which in reality won’t do much more than make your water look a bit clearer. If your ultimate goal is to keep bacteria, protozoa...
www.marinedepot.com
There are lots of UV sterilizers to choose from.