Hello!
Over the past days BTC has fallen quite a bit, also ETH. Any clue why? Seems to be opportunity to buy more.
Yes it is always wise decision to buy every alts that are in red during bloodbath, if you have bought at the time of your post than you are already in profit.
It may be profitable, but it is also risky. The volatility associated with bitcoins is huge, and the volatility associated with alts is much higher.
You just have to go to coinmarketcap.com to see how many altcoins are effectively dead.