Here’s Tony at the safety stop in a notable plankton bloom, at the end of a dive at Justin’s Caves. Fortunately the water was clean at the bottom, and even cleaner inshore on the landward side of the rocks!
[youtube=”http://www.youtube.com/watch?v=vtRLRI4TFXI&w=540″]
A strong south easterly wind that brings clear, nutrient rich water from deep offshore, followed by even a few windless hours of sunshine, will turn the surface waters of the sea on the Atlantic side of the Cape Peninsula to pea soup. Here’s a salutary example from a dive we did where the top 20 metres or so were thick, green sludge.