Raw cider w/ wild yeasts: growing surface molds

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Nursery Log

Oct 20, 2020
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Southern Oregon USA
We pressed about 20 gallons of cider on Oct 16.

The first thing observable was spots forming on the surface, growing into somewhat of a surface network. The next day, I could tell there were spots of green (probably trichoderma) sporulating, the whole surface looks like a petri dish... with some bubbles. I want to know two things; what to do to save the cider, and how to do it better in the future.
So this is happening in the primary fermentation. I've read that for the primary fermentation stage with cider, it is not necessary to fill the carboy all the way to the top, because excess oxygen would not harm the cider... So my ciders are in 12- and 24-gal fermentation buckets. but I'm thinking that another downside of this surface area is that it creates more space for molds to grow. Should i scrape off the surface contaminants and transfer it to a container with less surface area? If i fill a carboy enough would it be possible to wait for it to ferment enough to blow off the surface bubbles including the surface molds?

How is best to manage a raw un-sulfured batch of cider so this doesn't happen? Does this happen often with wild batches? At what point would you say these molds will ruin the cider (how bad is this)? With sulfites not being an option, and although I don't want a commercial yeast, would now be a good idea to try to pasteurize some/all of it and pitch a domestic yeast? Finally, I'm not familiar with primary fermentation in a mostly full carboy; is there a way to get a small surface area without causing a huge mess and having something to take care of/check on every day?