UV Sterilizer

Well, you need something to push the water through the unit. Many people attach it to the return of a canister filter. It is better to have it that way because you want filtered water going through the sterializer rather than unfiltered water because over time, it will cause it to clog up with gunk. The other way is with a powerhead, which just sucks water from the tank and forces it in a direction you chose. People use the for water circulation, but you can attach a hose to it for the u.v. Either way is fine, but again, if you have a canister filter, hook the u.v. up to it.

Yea, you put the water comming from the filter in one end and the hose to the tank in the other. Very easy.

Why are you thinking of adding a UV?

This thread might be better suited for the Freshwater Products & DIY forum.

UV sterilizers use a high intensity light to kill free floating organisms in the water. What you do is take the hose that comes from your canister filter and make that water go through the UV sterilizer before it re-enters your tank. It just basically utilizes the canister instead of a separate water pump. For those people without a canister you can just buy an inline pump.