Answer: Ivy cuttings may be successfully rooted in water. It sounds like your cuttings may be suffering from a decay organism. You may need to discard this group as it is probably past saving. Start again with a clean container and fresh water. Take cuttings that are not too tender and succulent. Semi-hardwood cuttings work best. These are taken in the section of vine between the tender, succulent tissues near the tip and the woody older section toward the base. Semi hardwood tissue seems to callous and root better.
Some people have good luck with a pinch of rooting hormone disolved in the water or by using willow water. This is a homemade solution made by collecting shoots from a willow tree, cutting them in to 6" lengths and soaking a handfull of them for a day in a quart of water. Next, remove the willow shoots and use the water to root cuttings. Try it and see how it works for you.
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