I think it's time to keep ethereum. Since Ethereum went lower than $300 a lot of investors talked about overpriced Ethereum, but the price $250-300 is really low, it would be $600 minimum.
I think it still takes a very long time, ethereum will return again for $ 600
can be seen to date the weakening price of ethereum for $ 300 has been more than half a year, and it will last for some time.
I also guess that if November or December market looks good. Then ETH can grow to 500$ and end in 2018. But if that does not happen then surely in 2019 ETH will remain below price 250$ and last until the end of the year.