Often this has to do with the plant not being able to get enough nutrition from the current soil.
My advice is to re-pot the plants in fresh pond soil with nutrition. Then put the plants back in the pond a little less deep.
Often this has to do with the plant not being able to get enough nutrition from the current soil.
My advice is to re-pot the plants in fresh pond soil with nutrition. Then put the plants back in the pond a little less deep.