We added a UV sterilizer to our 200 gallon system. Almost a year old now with livestock from the easy list with the exception of a Copperband Butterfly. We intend to add more fish, possibly some from the intermediate difficulty list.
To date, we do not quarantine new livestock. For example, how would we quarantine a fish that needs a 100 gallons of swimming room just to avoid undue stress? A strategy we employ is to purchase from reputable local fish stores (LFS) that in turn purchase from reputable wholesalers (QM for example), and fish that have been in stock at the retailer for at least a few days, that are eating, and appear healthy and disease free by sight.
To keep it simple, we mounted the unit to a board and laid then laid the board with the UV on top, across the sump. The sterilizer is securely attached to the board and the board is long enough so the unit can’t practically fall into the sump.
The UV unit was installed in such a way as to make it very easy to remove for cleaning and bulb maintenance and/or to get it out of the way for other tasks and maintenance in and around the sump.
Design theme: Make it as easy as possible and practical to perform maintenance. No excuses.
Inlet and outlet are positioned above the sump so any leaks drip into the sump. High enough so no splashing or bubbles hit the unit.
Using vinyl tubing, a small pump draws from the sump near the display tank drain, pushes water through the UV, and exits the near the return pump. The pump is selected to maximize dwell time, but not so flow of a flow rate as to risk overheating the UV bulb.