Bump. Bigger than you may realize.
Go to manufactures' web sites and read about the required relationships amongst:
1. Wattage
2. Water flow rates.
3. System volume
Sizing a UV system involves understanding exposure level requirements for germicidal sterilization by UV radiation. UV exposure levels are determined by matching up the wattage of a UV system with how slow or fast the water moves through the unit and how long it takes to achieve multiple passes of all of your system water through the sterilizer.
It is kind of like getting sunburned. If you step out naked into strong sun for only a moment you won't get sunburn damage to your skin. Yet on another day with less sun you can get scorched if you bask in it for hours. But if you have protective clothing you won't get burned on either day.
You are not doing anything to the water itself with UV radiation. You are only zapping things in the water. If the "thing" is wearing a protective shell, it will not get burned and killed off.
Single cell bacteria that do not have hard casings are the critters you can eradicate with UV germicidal radiation. You will not kill off fleas and ticks. You will not damage bacteria with hard coverings.
The little guy is not killed directly. Rather his DNA gets damaged. Then he cannot reproduce. Eventually the population fails from infertility of the masses.
Do not run out and buy a UV sterilizer. Read, learn, then choose a UV system with assistance from the manufacturer. If you cannot discuss this directly with the actual manufacturer then stay away from that brand. There are a couple of the best manufacturers right here in the USA and they make their sterilizers in America with american labor. They will talk with you and assure you get properly sized. If you live outside the USA these are still good brands for you, but you can check for more local brands.
Sizing is very important in UV sterization equipment. So is bulb life as that determines your recurring cost. Germicidal UV radiation is great stuff for an aquarium.
Size matters. So does quality.
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