Biological warfare?

"Bill Stock" wrote in message
...
I read something here a while ago about plants (Water Lettuce) and Algae
exchanging chemical attacks. Is there anything to this or is it just an old
wives tail? The reason I ask is that my Water Hyacinth is dying off, it's
all turning brown and mushy around the edges. The leaves that are healthy
seem to be a good colour, but the outside leaves and pontoons are all split
and brown. I've been adding trace elements and Potash for a few weeks and I
even added some Nitrates (5 PPM) last week. The roots are constantly
covered in Hair Algae, so I'm wondering if it is having some sort of
chemical effect on the WH. So far the Water Lettuce does not have any Algae
on the roots, but I suspect that's more a matter of duration. It's only
been in the pond for a few days. Salt s/b zero, but I'm tempted to check at
this point.

Any WH rejuvenation advice would be appreciated.

TIA


Thanks for all the suggestions. I should have mentioned that they are not
producing offspring, i.e.. they cover less area now than they did a few
weeks ago. They seem to have stabilized a bit since I added the Nitrates,
I'll see how they are doing on the weekend. The Nitrates are still around 5
PPM, which is a little surprising as I added 5+ on Sunday. I would have
thought the Algae would have taken off and consumed all the Nitrates, but
it's only marginally worse than it was. Although it has started to produce
gas (bubbles). The Lilies are just taking off though, they must cover 25% of
the pond from their two little pots.

The WH are getting lots of sun (over 30° C) most days and probably 8 hours
of direct sun. I may try a Miracle Grow bath as a last resort and then toss
them as RM and CB suggested, if they don't recover.