If a particular cryptocurrency is not suitable for long-term investment, then you can always go for short-term holding, ranging from anywhere between 1 month to 12 months. What is the need to engage in risky day trading? I am saying this because many of the altcoins are heavily manipulated and the prices can swing  by +/- 30% within a few hours. Unless you have an idea about the manipulation, it is very risky to be involved with them.