An old trader told me, to survive in the futures market, I must keep more than enough cash reserve in my a/c. So even the market suddenly crashed, I could still survive. He suggested at least 3 times the initial margin for one contract. For day trading NQ, if I keep $10,000(=500 points) for one contract, I could quite sure that it won't move so many points within one day(even for the Sep 11). Would you do this? Any guy doing so?