[Courgette1]

Hello.
This is my first post, I have just got a plot and it comes with a IBC water tank that the previous owner has left there, the owner went AWOL so I'm guessing that it's been sat there a good while.
It's full of water and I wouldn't like it to go to waste but is it safe to use? I don't like the idea of watering my veggies with contaminated water, legionnaires disease or other.
There are some water butts there too that I see have lot of squiggly lavae  swimming around in them.
What do I do?
Thank you for your help.

[Yorkie]

I'm not sure of the answer, but just wanted to say welcome to the site a nd congrats on your new lotty!

[Kleftiwallah]

Hello there Courgette1 and welcome. 
The lot of squiggly lavae you have could be mosquito lavae.  The easyest way to 'remove' them is place a few drops of washing up liquid on the surface, this will break down the surface tension and they will decend to the bottom.

Cheers,  Tony.

[Blewit]

Hello and welcome. Mozzy larvae in the barrels is probably an indicator that water's safe to use on plants, no chemicals etc. You could scoop some up with a container, drop them in the IBC and see if they survive. Also have a good sniff in the IBC.