Does someone has any suggestions how to make 17 BTC with 7 BTC starting capital in short period of time?
Try Forex bro, only forex can grow your btc significant but don't forget that forex also can deplete your btc in short time.
High Risk = High Money = High Loss

Forex is the easiest way to go from 7BTC to 0BTC. The profit margin is low and the risk is very high