Hi I am hoping for some help.

I have an anubias growing immersed in a small pond outdoors, but it’s developed brown spots on it.

The water temps during the day are about 8-10 degrees at the moment - maybe a little colder at night, but not by much since the pond is in full shade. So I’m wondering if this could just be too cold for the plant, or is it a disease?

It’s attached itself really nicely to a log so I don’t want to remove it but will it survive the cold?