Tether is being used to hedge in those kind of big fluctuations. However, if you are in for the long term, then why hedge it? And I do hope that you understand that crypto is really a speculative asset so there's a lot of fluctuations going on. And this kind of wild price swings is somewhat has advantage for us crypto traders. So I can't advise any altcoin, worst they are much unstable as bitcoin is. So it's better to just put your investment on bitcoin only and hold for long term.