Just one more thought on outdoor containers before I forget. Plants grow great outdoors in the summer. Water lettuce and Salvinia make great floaters. In that outdoor container put in fish that have tiny fry that are hard to feed. The plants will encourage natural infusoria microorganisms and the fry will be great. I did Bettas like that once and had the best crop of young ever. You won't even have to do anything special. Just being outside seems to make the fish and plants go ape.