if they look like the 1st then i would say they are. hindsight is just a wonderful thing lol! my grandfather always told me if you don`t learn something new everyday your not living. as far as your ppm it depends on your meter, they have no standard. the meter companies like hanna uses a .5 conversion rate while other use .7. over the years i`ve got to where i don`t check my ppm much if any at all. when i have troubles i may check it. i worry more about my ph. now you just getting started i would recommend you check anything. if you keep your ph inline the plant will tell you via the leaves what it needs, like the earler problem you had, after a while it just becomes second nature. on to the good stuff. man that group shot looks great, you`ve done a good job with those girls so far. i would start shopping around for a few cases of jars if you don`t already have `em.
now for a problem that might show up in a few weeks, it may or may not happen. the shiny air ducting you have may cause light hot spots. i had never seen it before till my last grow and it drove me crazy trying to figure out what was the cause of all of the burnt leaves i was having. i made a change in my garden area, i moved my filter and the light reflected off the ducting was burning the shit out of the 2 plants closest to it.
like i said you may not have any problem with it, and i wouldn`t change anything till the if or when it happens. i haven`t seen much of this happening since people were trying to cover cabinets with mirrors.