My dad and I were setting up my 75G and came across this.. At first we figured it was something that had died, but when I scooped it up in the net, it was moving in a snake like way? It takes a jelly like form when outside of the water, but pictured below you can see how it takes form. Just want to know if anyone knows anything about it, whether it's good or bad? Nudibranch? Suggestions?

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