Not sure if anyone else uses gutterguard, but i found this stuff at my local hardware store. It has a grooved side that fits perfectly over a standard glass pane, and the other side can be easily cut to fit with a decent pair of scissors. I found it much easier to work with than eggcrate, and it sits perfectly flush. You can't see it from the front. Felt it was relevent to the thread if it can help someone keep their fairy's wet cheaply and easily, and still allow for gas exchange/heat transfer.
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