Is UVC sterilizer necassery?

[sunnymau]

is UVC light nesaccery for a reef tank? will the UVC light kill good bacteria like nitrosomonas and nitrobacter? is yes, then why should we use UVC sterilizer?

[Golf]

1. UV sterilizer kills bacterias, both good and bad. But difference is good bacteria usually stays on the sand bed, LR, substrates, coral chips. So it is usually those "floating bad bacterias" that got killed by UV Sterilizer. I think there will be minimal killing of those good bacterias.

2. It also helps to make water clearer.

Kindly correct me if I am wrong...

[sunnymau]

if that is so, how many watt uv light should i use for my 250L tank?

[sunnymau]

may i also know why there is a black on the letter that i posted? what does it mean?

[FuEl]

Any phytoplankton or zooplankton passing thru the UV will get sterilized...if you know what i mean.

[sunnymau]

they are a kind food source for the fish is it? something like microalgea? pls correct me if im wrong.. will killing of the plankton cause chaos in the tank e.g lack of oxygen or food