All the plants in same soil and treated the same.Its the only one.haha.The plant is all brittle now.the leaves are still green but feel like paper.I think its a goner but will keep at it.I would flush the soil with heaps of fresh water (ph balanced) and see if it came good after that. Will help if overfeeding is the problem but that's only a weak guess. Are any of your ather plants showing signs of this problem bro?
Oh yeah what jss said, get it away from your other plants just in case it is a virus or similar.