[quote= but never considered lilies very useful, just decorative,
except for a bit of shade. [/QUOTE]

Humph.

Waterlilies protect fish from predators, providing cover
Waterlilies can moderate water temperatures 15°f cooler in a hot climate
Waterlilies are edible to a host of beneficial aquatic insects, providing a nutritious food chain
Waterlilies in themselves substantially improve water quality by absorbing surplus fertility. a well planted pond can deplete the very stuff that feeds algae blooms

A lot of ponds fail, they do not have a balanced ecology. Needless to say, folk with very limited experience of ponds and water gardening make more money selling pumps, junk and water squishing devices as a rather iffy 'life support' system for a pond, you tend to hear more noise plugging the very expensive and less efficient alternatives to a well planted pond...

Because that makes them more money

Regards, andy
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