ANchor worms, when they are large enough to see, look like clear straws. They do not float free, like tendrils of slime. They are anchored into the fish.
Water lilies can grow at depths. Depends on the type.
Most of my lilies are 18 inches or so.
But the "Magnum" Linsey Woods is in 48 inches of water. Not intentionally. I had her up on blocks, but she fell off.
She's the most successful single lily I have. HUGE blooms.