A hard Winter freeze inches deep will bump off the bulk of it, though it can ressurect from fragments that found their way tangled in deeper water, or spores stomped into mud.

Harsh mist spraying and netting works well enough on a smaller size pond.

If you keep the pond well topped up, cross fingers a period of heavy rain will help to flush it through an outflow

Azolla makes a useful mulch

Regards, andy
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