I call it green water but because I often type in the wrong word for it but it is phytoplankton or bugs that live on sun light.
If you read about it around the web, you will fine that it is pretty close to the bottom of the food chain. Zooplankton like rotifers , the next step in the chain, eats the phytoplankton and corals eat the zooplankton. They are used a lot for breeding fish as well. Unfortunately, as I studied up on culturing green water, I found out that culture crashing was common unless you take great care not to let certain bacteria get out of hand.
You can see what worley is doing with it on this site at:
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