Few rust spots 6.5 weeks into flower

So I found a few rust spots on maybe 5 leaves in 3 plants... I was just wondering at the end Of a plants life is it normal to show signs of deficiencies? I'm using GH 3 stage system micro grow bloom. And have been adding more bloom each time I feed. I have one more nute feed then it's time to flush for 2 weeks.

Last few pics are of the rust spots
Link to pics---https://www.rollitup.org/stealth-micro-cab-growing/500956-first-cab-grow-pics-hopfully-2.html

yes br0 if toomuch bl00m u get mg def top dress da soilz with epsom salts magnezium sulfate omg or add mg to water 1tsp per 2 litres
peece
and dont over doz da bloom foodz omg