There are many types of seaweed which have many similar properties. However, blue green spirulina is believed to have RNA which is more advantageous to the nervous system than of the other seaweeds.
If you are 100 to 150 pounds, I would take 6 spirulina plus 1 extra for every 2 moons which are missing. I would also add 1 additional spirulina for every 50 pounds of body weight.
It is EXTREMELY important that you make sure the quality of the spirulina is very high. Since spriulina absorbs radiation and toxins, the company from whom you buy should test for radiation and heavy metals!