Ok, I might have found out why cryptos fell during the night. Apparently there has been a major hack on the Japanese crypto exchange Coincheck. A staggering $400 Million has been reported stolen and everything seems to have been stolen from from NEM, the 10th largest cryptocurrency in terms of market cap. Here is what happened to NEM during the night:
It looks like NEM has recovered a bit, it was down 20% on Coincheck at one time. This chart Im showing is from Poloniex.
Anyways, the lesson to be learned from this is that you should never keep any large amount of any crypto on any exchange any longer than necessary.
Use hard wallets or paper wallets, those are the safest options as of now.
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