Hi Kevin, so sorry to hear about the unfortunate demise of your previous starter! If your new starter is forming a dry film on the surface it sounds like you need to cover it a little more securely. The reason we say to "cover loosely" isn't because the starter needs airflow in order to ferment properly (it doesn't), but because fermentation gases can build up in a tightly lidded container and cause the lid to pop off. As long as you leave sufficient room for fermentation gases to collect, and you open the jar now and then to vent the gases, it's fine to use a lid. You could also cover the top of the container with plastic wrap, which will flex. 

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