Currently I own a lot of altcoin, I bought them at ico. My account is being downgraded several times. There are many people who say bitcoin will continue to decrease, so altcoin prices also decreased compared to USDT. So now, should I sell them and wait for the price to buy back? Give me advice 
before you buy a potential altcoin or not if you buy a coin that has the potential why not keep on holding it Market conditions not forever down , just a matter of time, because the market is in trend up even though it's not high