This is because of the FUDs spreading in the internet and in the NEWS. Another reason maybe considered is that the China government already took action which may shock anyone living in China. China already implemented the total crypto ban.
Yes, I agree that china implemented the total ban for crypto that's maybe the reason behind the fall down of altcoin. There is no assurance for being stable of altcoin. When the price of bitcoin is affected it will also affect the price of altcoin because the two coin are related into each other. Maybe in the next month, the exchange of altcoin will rise up. I hope so.