curious how deep down a typical plankton bloom is from the surface in a non aerated pond. i have a trash rack around my spillway pipe that is approx 8 ft down from the surface. right now the water flowing out the pipe is as green as my pond surface. so it has to be at least 8 ft deep of green bloom.
i have an extremely dense bloom now. last time i checked it was 18" on the secchi but i can tell it is way more green now. and to top it off we had about 5 inches of rain in the last 3 days. lots of flow thru right now, but it is still green.

During the spring I'd be green with envy at your bloom, Scott. Not so much now, though.

I can not answer the how deep question, but you can sample your pond and find out for sure. Take a length of hose and get out on the dock or in a boat. While the hose is out of the water, put your thumb over one end then drop the other end straight down until you get to the test depth, let your thumb off which allows water from the test depth to fill the hose up to the surface. Put your thumb back over the end and pull your hose up and then put the water in a container by releasing your thumb while the other end is in the container. If the water is green at that test depth then go another foot deeper for the next sample.

I guess this would be a lot easier with a pump set-up, but I'm thinking quick, cheap, down and dirty.