Bitcoin to crypto currency is like a dollar to fiat. So whatever happens it is here to stay, at least for now. Rule of thumb is invest only what you are ready to loose., and don't worry if all currencies going down that's ok they will go up also. You should be worried if one currency is going down really fast... better to sell it before you loose significant amount.
But I see some new coins like ENG (Enigma) and Medibloc very good projects and will go up in the near future.
Tron is going down very fast. So is NEBL.
If you don't need any money right now,i suggest you just hold all those coin that you have.There will be a time they will be pumped in the future,assuming you have a good coin in the development and updates.But if you think that you have a shit coin,just dump all of them and start invest in a good coin,there's many out there,go to speculation sub forum and read there.
I heard Tron was a scam coin.