Pivx making a 20x? it is impossible mate, you are so optimistic about the price.
And if you really think that it will be making a 20x, then why dont you try to get a huge amount of money and then try to invest that money in there?
Just think about it, 20x of $15 is just a little amount of money, 300 dollars are worth nothing, you can just try to get more money and then that 20x is going to make the whole difference.
And yes, try to sell some coins and invest more money in the strongest coins that you are investing now, having $500 in more than 5 altcoins is just a waste of time.