First off they took time to show any damage so in turn the opposite is true your ph is within range and ppm is about right I would give them a few days and add some Cal-mag since what you have is a a magnesium def triggered by low ppm it will take time to show any improvement
read this article and be patient improvement will come but damage already caused may still continue to present itself. By the time you catch most nutrient deficiencies you are likely a week behind new growth is always the measure not older growth
Thanks @Donaldj things are looking much better after adding CalMag in the last couple res changes. The plants are now a couple weeks into flowering and doing good.
I was wondering what peoples thoughts on water level are during flowering is. I have read a lot of conflicting info. Seems like some people swear by having the water level 1/2" or more below net pot level to let a portion of the root mass hang in oxygen. Others says long as you have enough DO (from a good pump and enough air stones) then you can fill all the way up.
I have a decent air pump and 4 air stones in the 18 gal reservoir. At first I was letting the roots hang a bit (Water level about 1" below net pot), but the hanging portion looked kinda dark (tan/brownish) so I started submerging the whole root mass by filling to the bottom of the net pot. The roots look good now. I understand the necessary water level changes during germination, early veg, etc, but now that I have a well developed root system and the plants are flowering I am wondering how the water level affects the plants during flowering and if exposing the hanging roots would provide any benefit.
This is best practice since roots are thickest around trunk and air doesn’t move well through the super thick mass also the newest roots and finer roots absorb nutrients and water best those tend to be at bottom
also the newest roots and finer roots absorb nutrients and water best those tend to be at bottom