What you're doing is daytrading. If you're in the U.S., then you're done trading for the entire week, because one more trade and you'll have broken the law. Why? Only 3 daytrades are allowed in a five-day rolling period unless you have more than $25k cash.

Also, if you happen to have a cash-only account (and I don't know why you would if you have $20k to spend), then you're also guilty of free-riding which is an additional big no-no.