Timmy, you should be fine, the solid safety covers have a vent in the center, which will allow any gasses to pass (or should I have said, any g***ses to p***). A number of people run their pool with the mesh safety cover on with no problems, the only problem I can see is if the water gets a little low and you start drawing air in through the skimmer, but I imagine that your water is still at operational level.
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