Somewhat to my surprise, the green bloom has returned. I did not think it was likely, in Winter.

Went out in the dingy, yesterday, to check the screen of the pump, as water flow has reduced significantly, in the flowforms. Very little detritus to brush off, so that's not the cause of the diminished flow.

Nice sentiments expressed - thanks - but Barbara died a while ago, now (2009). That did not stop the labour-of-love, of course.