Calcium supplementation for mystery snail?

I was doing a reading mystery snail care, and someone had said that a calcium supplement or iodine is good for their shells. My question is: Are supplements safe for aquarium life? (Tetras, mollies, gouramis, etc) I'm sure I can ask someone at Petco when I go, but I thought I would get other opinions. Thanks.

not rely on what employees of the pet store tell you, anyone can work there so you probably take advice from someone who knows as much or even less than you. I had mystery snails, and if the calcium is a good idea to use for coral calcium, read the ingredients to make sure it has nothing in it, in addition to calcium, while calcium and it is only liquid will not damage freshwater tanks. You also can crush some shells and add to increased calcium slooooow.

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