1 bag of Daphnia magna.

"Daphnia magna is a typical water flea of the genus Daphnia. The females reach up to 5 mm in size, the males about 2 mm, thus they are among the largest species in the genus.^[2] The body is protected by a translucent carapace made of chitin, a transparent polysaccharide.^[3] It has a ventral opening and five pairs of thoracic limbs, used to help the filtering process.^[4] Spike rows run along the back of the carapace. The intestine is hook-shaped and has two digestive ceca. The head has two antennae and a large compound eye.^[5][6]"

Wikipedia