Small, flowers

Nothing wrong, bottleneck somewhere in your overall cycle. If I was a betting man I'd guess you have oxygen problems. Either that your ratio of nutrients is skewed causing ph to drift out of range. If it was solely a nute def then symptoms would appear linked to its mobility. Its pH skew, or antagonized lockout. It is surprisingly easy to create an anoxic (zero oxygen) environment in a plant's root zone, even when attempting to oxygenate it. While oxygen is essential for root respiration, the physical properties of water make it a "lockout" mechanism when the medium is oversaturated, because oxygen diffuses 10,000 times slower in water than in air and 320,000 times slower soil saturated past a point. Gotta make sure by time 🌙 night comes the medium is in a sweet spot for oxygenation and the air has adequate space for more moisture and rh remains controlled. Failure to do so will gradually overtime if water is not moving fast enough or is getting trapped anywhere in those pots its just a matter of time. Keeping close tabs on ambient humidity day and night during the flowering period is crucial for indoor. A thick, shaded canopy restricts airflow and reduces evaporation of medium. In this phase, high relative humidity (RH) not creating adequate wet dry cycle can slowly start to break down the entire energetic process that's what I see. The transition of microorganisms from aerobic (oxygen-rich) to anaerobic (oxygen-deprived) conditions results in a significantly slower breakdown, plant runs on 10%20% potential, acids release in form of lacric acid skewing ph acidic. 40% of all carbon a cannabis plant captures is exuded into the soil to feed Micros, this slowly increases moisture retention as time goes on. If you are also delivering nutrients organically then the microorganisms will also directly compete with the plant for oxygen at a higher rate than compared to synthetic delivery. Very very common to see 4th week of flower onwards a complete breakdown of oxygen. Slowly over time leads to this exact m.o. Apologies for long winded answer, but it is a long complex answer and if you don't wanna see the same problem every grow going forward I'd suggest you take the time to study up on negative pressure and apply it to your tent at nights. Or just ignore everything I said and add calmag.