Chironex

Actually, that's probably a good thing! You have no rot now and it will certainly grow back from the pstem you have left. Believe it or not, it is healthier now than before.
Hard pill to swallow, isn't it? I would not water it for a month, at least. I have cut them back to the corm and they came right back up in a week. Keep in mind that it's winter now, so don't expect it to grow fast, but you did the right thing. Since there are no leaves, it will not require more water for quite awhile.

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Scot