I don't think that is right time to buy altcoins especially what happened today if BTC keep bleeding than next turn will be on altcoins market. Altcoins also need to get little correction although it is maintaining very well as comparison with Bitcoin.
Altcoins weren't maintaining good market in comparison to bitcoin. Right now bitcoin market is far better than altcoins even after such a drastic price fall. If there happens price fall low to $6500 there is more chances for the price to reach $5000. Maybe this can be a price correction based on the upcoming halving scheduled for 2020. As there is crash in the market of bitcoin, same gets followed by altcoins. Good thing is to wait a week's time and get into investing on altcoins.