Water Lettuce Problem
Doug says
Stop the fountain circulating. ;-) For the most part, floating plants like this do not like being wet from the splashing or being in fairly quick moving water.
You'll also find the need to constantly add water to this fountain is keeping the water fairly full of chlorine - another small problem.
And to top this off - 6 hours of sunlight is pretty much at the lower end of the sunlight level for this plant.
You could move the fountain - turn off the water but then you'll have a pond. :-)
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