It depends on how much risk you can take. If you trade with a money you cannot afford to lose, better take out the 500USD after your gains as you can leave either with a win or a lose with your another 500USD profit. But if you can afford to lose 500USD, then risk it, but keep in mind that not all times you can win. Again, never be frustrated after loses. But never trade at first place without a trading plan and without following that plan. Goodluck mate!