The time to buy ethereum will always depend on you , depends on the risk you can take. As you see ethereum value goes down, I dont think thats is good but if you think in the positive side it is in good for some investors to buy more ethereum tokens and hold and wait for ethereum to recover again.
But if we buy in we do not know when they will recover, so our holdings have no purpose, is really difficult for the market today, I find that the market is very difficult We mainly have new knowledge and experience to get profit from the market today