My water lilies used to grow and multiply at an alarming rate-they were very happy! Two years ago they started to die off, The corms of the dead plants are soft, and turn bright red, they is no sign of insects in the pots, Last year, I tried re-potting the plants that had survived, I used regular garden soil, and gave each pot a Laguna water plant fertilizer stake, This year there was more dead plants. The ones that did survive look sickly and probably will not survive the summer. The fish in the pond are happy and content, as are the other plants- it is only the water lilies that are affected.