This year most of my hyacinth have satyed in the yellow rather than
green phase. And they have not grown as tall as usual. I tried
potash. It helped a few of them. The water celery is thriving.
Could this be an iron issue? Any suggestions as to a good source for
iron, if that is likely to be it? I have ironite that I use in the
garden, but I don't know if it would have bad effects for trace
minerals if used in the pond.

Suggestions?

Jim