"Karen Mullen" wrote in message
...
What is the water lettuce missing if my WH is nice and green but the edges
of
my WL are turning yellow. All other plants look great.

Hi, Karen--

I had this problem all pond season, and the potash didn't do anything to
assist in greening the lettuces, nor did a trace element mixture. I ended
up finding clouds of little black gnats over all the lettuces as well as
some amongst the leaves. I think they were the culprits. Take a good look
at your plants and see if the bugs are camping out in yours, too.

NJ
zone 5b