The distilled water is good because it will make cleaning easier (at least no mineral residue). I have a filter on my sink water & that is good enough for me. I haven't had any issues, but everyone's water is different. Since the base is plastic, if a mineral residue starts to build up, you can always clean it with some vinegar.
The shelf liner works perfectly during hatching. I strongly recommend it - especially if you're hatching bantams or quail whose feet could go through the grate. The shelf liner also helped the turner handle tiny quail eggs. Without it, those little eggs did somersaults and even hopped the rails.
However when I used it during incubation of my regular large eggs, the shelf liner did leave a shine around the center of the egg some time after the 1st week. Not sure if it rubbed off the bloom or if something got deposited onto the egg. The eggs hatched OK but it worried me a little.
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