Currently, I am trying to complete the game without touching the Coconut Resource. It's been a success so far! Also, I had a strange technique of completing Puzzle 7. I kept my water clear (unplagued by algae) until I got enough Tech Points to purchase (only highlight the white text if you want to know the how I solved Puzzle 7, as I don't want to spoil it for anyone) Level 3 Farming. Then I created a Mass Fishing expedition! So I has all my villagers on Fishing, until the water got plagued by algae. A second later, I purchased the the required Tech and put the algae fish from the diving pool in the clouded water. So, for the entire game, the ocean was only plagued with algae for about 5 min!!