UV C for disinfecting my water tank

[Home Improvement]

I have water tank with 1 meter cubic capacity and a UV C lamp 32W. how long does the UV C lamp need to be turned on to do an effective germicide irradiation on my water tank to kill bacteria, etc, but most importantly, spores of mold, and fungi which would clog the pipes.
I assume that once the spores inside water tank have been killed by UV C, then no matter how much the storage tank is exposed to sunlight, it is guaranteed there will be no mold anymore.

Thanks

 

[Reach4]

A non-pressurized tank gets new spores from the air.

If this is a pressurized tank, you would still have to kill the spores that were in the pipes. That would take a liquid, usually chlorine bleach ideally with the water pH reduced to 5.5.

 

[Sponsor]

 

[ditttohead]

Start with this short article to get a basic understanding of UV. A uv amp in a tank... it has to do with how much exposure is available by the lamp. If the lamp is in a tiny tank, then it might have a fairly quick kill rate. If it is in a large tank with dirty water, it is unlikely to have any affect. Too many variables for anyone to be able to formulate a reasonable answer. We need a lot more information on your system design. https://view.publitas.com/impact-water-products/2018-catalog-final/page/274-275

 

[Home Improvement]

it's a tank with clear water.
the system can be shown here
https://terrylove.com/forums/index.php?threads/effect-on-pump-position.73054/

the diagram in the first post, the pump position is number #1.
the tank on the roof is the one with mold problem
pretty sure this system is air-proof, so I dont expect spores from the air. unless I'm wrong?
and no, this is not pressurized tank, just normal tank
thanks