I prefer not to use my profit because it's already a profit, with your initial balance, it's better not to use it so you can play in peace. I think it's better when your profit is already above the initial amount or equal to it meaning if you deposited, 0.1 and when you gambled and made it to 0.2, and I will withdraw already the 0.1 profit and play again with my initial bet.
So you play against also for your profit. Because you deposit 0.1
BTC then if this would doubled and make 0.2
BTC you will withdraw the 0.1
BTC that its your bankroll. And you will again the remaining that its your profit? 0.1
BTC am i right? Because that's what i'm thingking