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Cal Hypo does not have CYA -- but it does leave calcium in your water.
Trichlor pucks do contain CYA. Each puck will add 2 ppm CYA to your pool volume.
Metals on the pool wall depends on what metal it is. Read Stains in Your Pool - Trouble Free Pool
I suggest you read ABC's of Pool Water Chemistry and consider reviewing the entire Pool School eBook.
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