Phytoplankton
(This is a producer so it uses photosynthesis to make it's own food, which is eventually passed down the food chain when the phyoplankton is eaten.)
Zooplankton
Bream
Flat Nose Catfish
Goliath Tigerfish
Bacteria
(This is a decomposer so after the Goliath tiger fish dies it will decompose the body)