I use $5.00 each re-purposed plastic barrels and dip the water out with a couple of 2.5 gallon buckets. This water is reserved for my potted plants so this method works fine for me. I got tired of fighting with the removal of accumulated debris on top of my screen cover so last year I experimented with using .12 each fish for mosquito larvae control. It worked great!
Here they are; inside for the winter.
