Question on UV sterilizers......

[MarineGirl411]

I heard from a local member of our fish group that it does not matter what size UV sterilizer you have as long as the flow through it is sized correctly. Is this true? A 15 watt sterilizer was used on a 180+ gallon system using an MJ900. Is there any benefit from this at all? The reason why I am asking is I am looking for a sterilizer. Thank you. =)

[2006]

I heard from a local member of our fish group that it does not matter what size UV sterilizer you have as long as the flow through it is sized correctly. Is this true?

That is incorrect.

Lower wattage UV's need lower flow to be effective. However if the flow is insufficient than not all of the water will pass through the UV in a 24 hour period if you factor in mixing.

This is why higher wattage UV's must be used on bigger systems.

You need to use a pump capable of moving 140gph for a 180 gallon system to ensure >99% of the entire system volume passes through the filter 2x day.

At 140gph you would need a sterilizer of about 100 watts to kill parasites.

Of course if you only want to kill bacteria you can use a sterilizer less then half this size.

[MarineGirl411]

Can you recommend one? I hear Emperor Aquatics have more contact time with the UV.