Question on Coralife UV install

[calcnerd]

I just upped my UV sterilizer to the 18w (good for 200-400gph) for my Fluval 405 on my 50 gallon due to the gph flow of the filter & not wanting to restrict it.

It's up & running...is there a way to tell if it's working?

 

[KaiserSousay]

its a 15w

OK, that bumps it to 150gph, more or less, for max death dealing.
Figure best usage at 1 watt per 10gph of flow.
So, 15watts X 10 would be 150gph.
At full flow from your canister it might kill free floating algae or not, but would have little effect on the nasty microorganisms.
Could have sworn that PDF you linked was for a 9 watt unit, which would have been 90gph.

 

[FishNCash]

If the lights is on then it's work. You'll notice the water is slightly clearer with an UV running. Connect the UV at the output of the canister so your UV wouldn't be dirty as fast.

 

[Toby_H]

The "max flow rate" of a UV has absolutely nothign to do with efficiency... this is the maximum amoutn of pressure that the housing is rated for before it leaks...

A flow rate of 10 gph per 1W of UV strength will allow for the full range of benefits a UV can offer. Higher flow rates will make the UV less efficient. So if you want to kill parasites, then do not exceed 10 gph per 1W (or 150 gph for 15W, or 180 gph for 18W)...


Keep in mind the UV-C will degrade to nothing long before the bulb stops illuminating. When the lamp is new, you know it's workign when the light is on. But after abotu a year, the UV bulb will run out of UV and will just be a plain old light bulb.