uv sterilizer

Hi
After the filter . The cleaner the water the more effective it will be . Does it have a recommended flow rate??
gary
 
Neither.
Generally the flow is too fast to allow the UV to do anything.
Dwell time (length of time a given bit is exposed to the UV radiation) is what kills. Dwell time for a UV unit attached to a filter is only long enough to kill suspended algae. You're not even annoying most species of bacteria.
 
Don't know what kind of pump you're using, but if it's a water circulation pump (such as the Hydor Koralia) situated to direct water flow across the front glass of the tank, for example, then place your UV at the rear corner of the tank, fully opposite to, and in the direction of the flow, to enable the UV to pick up and destroy all the free-floating algae dislodged by the pump.
Helps to control algae, especially the film/dust algae.
 
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