One technique I tried with a customer last year after their liner's seam failed is to wait until a snowstorm, and then attempt to go with the 'old fashioned' method of packing it down and spraying it. You'll need very cold temps for the entirety of the season, as a thaw will expose the holes you've found already, but if your climate will support it, it's worth a shot.
I'm Joe from Backyard-Hockey.com and EliteRinks.com.
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