Answer: I was not familiar with either of those, but a quick research shows that Cheshunt is a town in England, the other is a chemical formulation offered in Europe. I don't know if there is a US equivalent. In general, neither type of treatment would be recommended on a routine basis. Damping off can usually be avoided by following good seed starting practices, and plants that are watered and potted appropriately would not normally encounter root rot. If there are specific problems with certain plants, we would be glad to try to help you trouble shoot if you ask again through the Q&A.
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