do you think ETH will go down to 400$
The $ 400 price i think is too low for ETH's ability. Because ETH is the best quality Altcoins after Bitcoin and the current price of ETH is very cheap. So i think ETH will be $ 1,000 by the end of this year.
It is still too early to confirm this as the demand for Cryptocurency investment this year is very small and investors are depressed the current market because prices can not recover well this year. I personally expect the ETH can reach $ 1000 in 2019 because this is the time when there will be many events that greatly affect Cryptocurrency.
seeing ethereum's price increase today,
I'm sure ethereum will return to the level of 400 $ later, maybe October