Here's what I was told about water hyacinth....
They are "trash" plants and can survive in the most mucky, foul, stagnant conditions. They're illegal here in Texas, because they get into the waterways and reproduce like crazy and clog everything up over acres and acres of water surface.
Because they live by filtering out the impurities from pond water, they won't generally do well in the average filtered and well-cared-for hobbiest's pond.
I believe this may be true. They will NOT thrive in my koi pond, even when I put them in a basket to keep their roots away from the fish.
But in those shallow, cramped tubs full of tadpole poop, which don't get cleaned too frequently (it's a real drag seperating the tadpoles from the muck on the bottom!), there the WH is going rampant.
Perhaps there ARE different varieties.... That could explain why some ponders do have WH doing well in thier ponds, but others of us have to stick it in old, nasty water.
Same thing with water lettuce, BTW. The ONLY place I have it growing is a tiny, shallow saucer meant to go under a flower pot. It's crowded and very full of fallen leaves on the bottom. The WL is huge, propegating like crazy, and a very nice green. If I put some in any of my cleaner ponds or even the tadpole tubs, it yellows and wanes and eventually dies.
