There are 3-4 common seaweeds. They are waiwai'ole, ogo, limu kohu and 'opihi seaweed. Another word for seaweed is limu, which is the Hawaiian word for seaweed.

Limu is found in the deep and the shallow parts of the water. The majority of limu are edible. Limu is loaded with iron but if you eat too much limu it could lead to high blood pressure. Some limu are very slimy but some are very grippy like ogo, waiwai'ole and limu kohu. The waiwai'ole is found 6-8 ft deep in the water. Waiwai'ole is a green spongy limu. It is only found in certain places unlike some other limu.

Most of the limu is found only in certain parts of the ocean, but the opihi limu is found in many places. Opihi limu is mixed up with opihi and people eat it.

Limu kohu is very strong when you eat it so you have to soak it in water for a couple of hours before preparing it to eat. Limu kohu is used in raw fish. People would mix up limu kohu and fish, then they would eat it. It is usually found on the reef and only in certain places.

The ogo limu also has to be soaked in water or else you would have a very bitter taste when you eat it. The ogo is a reddish brown color. The ogo is found in the deep and the shallow part of the water. The ogo is only found on Oahu or Maui.

There are fresh water limu just like konbu.