UV units: how long do you use?

[kaaikop]

Was just wondering how you guys use your UV units. I have read that UV
can interfere with ferts, mainly iron.

Do you use it 24/7, one week/month or only when required?
and why... 8) Thanks!

 

[malkore]

the only planted tank person who runs a UV that I know, only runs it 8 hours a night when the lights are off.

UV's aren't necessary in FW, or FW planted tanks.

 

[kaaikop]

So that makes two of us 8)

 

[travis simonson]

I may be the guy Malkore is referring to. I've heard that UV can increase the oxidation of iron and other trace elements so I only run mine on an alternating schedule with my tank lights (i.e. tanks lights on - UV off; UV on - tank lights off). I dose iron/traces in the morning when the lights come on and the UV goes off so the plants have a full light cycle to assimilate the ferts before the UV comes on again and the chance of trace oxidation is dimished. It works great and the plants show no signs of trace deficiency. I have also never had a problem with green water or ich. In fact (knocks on wood) I've never had a sick fish since I started using the UV