It depends.
Personally, i think it is a good time to invest in altcoin with some big declines, but which show resistant in this last weeks (when btc was falling from 6k$).
Some good example is IOTA, which was at 7k sato, then fell to just 6200satosh, but immediately jumps back to 7k+satoshi.
Also think about leaving money in just BTC, coz i personally dont suggest going now into fiat, or stable coins. (btc already fell really low)

Nowadays i'm looking for some really strong teams with a lot of money, which are now really low in rank because of delays in delivering some complicated product. 
Here, a good example is Lisk. Lisk was ranked by Chinese in top10 best technologies, but by market cap, Lisk is top30+ and -95%+ from ATH