[Clearview]

I have a water tank in my garden which contains my purified water. Although I keep it covered with a tarp there is a green film developing on the base of the tank. It doesn't seem to affect the water purity but i'd like to keep the tank clean. Any recommendations on how to do this? A drop of bleach perhaps??

[Smurf]

I normally just pressure wash mine out with purified water once in a while.  Being 1000 ltr Ibc's with the larger lids they are very easy and quick to do. You could bleach them but to be honest I don’t bother anymore.

[Alexns]

What would you recommend to clean an IBC tank that has previously held chemicals. I bought mine second hand on ebay and it stinks of whatever has been in there before!