Okay so i understand that all bitcoin i receive is taxed as income and then taxed for capital gain once i sell but say this happens- I loan 10 bitcoins out and then at the end of the month i get 11 bitcoins back with the 10 being my principal and the extra 1 as interest. would i only need to pay taxes for the 1 bitcoin since i payed taxes already on my other 10 or is there something wrong with my assumptions?