I also throw it straight on the garden.
this should be in the Pond Forum but: Have you tried adding a bag of barley straw to the pond to keep down algae? It works like a charm. I've taken a lidded plastic box that greens come in at the store, punched more holes in it, filled it with the straw and wired it shut. It cleared the pond in about 2 days (this is a small hand-dug pond with no filtering but a fountain helps aerate the water. The water needs to be about 70 degrees F. for it to work well. I've also used old nylon stockings to hold the straw. The containers should be kept towards the surface of the water I've been told, not on the pond bottom, to get the best result, but I cannot remember the reason. Maybe oxygen?