The message
from "Peter Stockdale" contains these words:

No more than in outside butts which I also use.(for outside plants).
This problem is significantly reduced by using dark coloured butts.
My main outside "butt" (5000k gallons) also has a black polythene cover to
eliminate algae totally.

I should think that a 5,000,000 gallon butt would be kept quite clear by
keeping giant catfish in it...

--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
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