Does UV-C harms bacteria?

[wheelsdeal]

Hello.I just set up my first freshwater aquarium 350-400 liters and i am currently in the cycling process.I have installed a 18w UV-C from JBL and was thinking of running it like 2 hours in the morning via timer.Somewhere though i read that UV lamps can harm usefull bacteria specifically at cycling process.I also read that it harms liquid fertilizer.Is this correct?And whats the best time to run it?I really didnt have anyone to advise me in all the setup process but i am a quick learner and as you are the experts i hope you can point me in the right direction.Thank you

 

[Lornek8]

Nope won't harm beneficial bacteria. Despite sometimes popular opinion, very little beneficial bacteria is free-floating in the tank water. The beneficial bacteria responsible for the break-down of fish waste is found in the filters and/or on hard surfaces. The bacteria must pass through the UV in order to get affected and thus beneficial bacteria colonizing filters will not get harmed.

Whenever I used a UV I simply ran it 24/7. Don't think there is any time that is more effective to run filters at then others.

UV can affect anything that passes through it. Though I am not sure, it may be possible for liquid fertilizers to be affected by the UV.

 

[wheelsdeal]

Nope won't harm beneficial bacteria. Despite sometimes popular opinion, very little beneficial bacteria is free-floating in the tank water. The beneficial bacteria responsible for the break-down of fish waste is found in the filters and/or on hard surfaces. The bacteria must pass through the UV in order to get affected and thus beneficial bacteria colonizing filters will not get harmed.

Whenever I used a UV I simply ran it 24/7. Don't think there is any time that is more effective to run filters at then others.

UV can affect anything that passes through it. Though I am not sure, it may be possible for liquid fertilizers to be affected by the UV.

Yea seems logical since the bacteria lives in the filter.I still have to figure out about the fertilizers but thanks for your response.