Here's my experince with martingale. If I have say 0.02 (or 2M sats) in balance and if I'm playing simple 50% win chance, I start with 1k sats and if I lose I double the bet. In most cases you will have not more than 7-8 reds with that winning chance, so when you bet 128k or 256k you win at last recovering all your losses and having +1k (your initial bet). With that strategy you can easily go from 2M to 3M most of the time, BUT when you have 13 or 14 reds in a row (which happened to me several times) you'll lose everything. And the thing is you never know when those 13 or 14 reds in a row will happen, you can have them when you just begun betting.

In short: martingale is a road to hell. )