uv sterilizer

[45ZoaGarden]

really dont know what to do spent alot of $$$$$ on this build

I understand. You should be able to get a 600gph pump for around $40 and pick up a ball valve to turn down the flow. Your current uv is fine. You just need more flow

 

[vetteguy53081]

Flow and wattage are both essential. A UV light is an optional piece of equipment for preventative use, and should be used as that. Many reefers make the mistake of purchasing one and then find out that parasites are still in the aquarium. I would suggest that the use of a UV Sterilizer should be thought through very seriously as to what your goal is with one.
If your tanks is doing fine, and you don’t have constant outbreaks of disease and parasites, or algae blooms, then the money you would spend on it could be used for a reactor, scrubber and such.
What wattage to go with is decided by the size of the aquarium you plan to use it on. The unofficial rule of thumb in determining the wattage is 10 watts per 75 gallons water volume for saltwater application and 10 watts for every 150 gallons for freshwater closed systems.
Flow through the UV Sterilizer is what determines the kill ratio of the microorganisms. Too fast, and they slip right through. Too slow, and the water can heat up the aquarium more than intended and lessen the life of the bulb. When choosing the speed for flow, I have found it best to go with the manufacturers minimum flow rating and increase the flow 50gph. I have found this to be most effective. If you find that it is causing a heat problem, you can increase the flow 50 GPH or so until the heat is not an issue. The key is to stay under the maximum effective flow rate by 50gph. This will present the best kill ratio.
As Sarah24 suggested, I too would recommend getting variable flow pump to be able to adjust the flow. You will want to get the pump rated for just under the maximum flow suggested for the UV unit. so, if 500 gph is the maximum flow rating from the manufacturer, you may want to get a 450 gph pump. This will give you the ability to adjust the flow accordingly if heat becomes an issue.








References:
Vincent B. Hargraves, The Complete Book Of The Marine Aquarium; Salamander Books 2002