DWC vs Soil - Blue Dream’matic

Problem 1- Brown dots are calmag or rather WERE calmag issues if the new growth is absent of said dots.. in December, because of growing in solution, calcium, magnesium and iron can get locked out easily and quickly. Maintaining a pH at 5.8-6.0 for veg and 5.4-5.8 for flower as well as water changes ever so often ( timing is dependent on the size of your rezivoirs and number and size of plant(s) per rezivoir. ) Solution ppm should be 800-900 for hard veg, 500-600 for early veg, and 1050 to 1200 ppm for deep flower. When changing out water, aim for a ppm lower than max to leave room for calmag between water changes. I usually go by the 2 top up change method, when the equivalent of the whole rezivoir has been added through watering, ex 5 gal bucker, over 1 week I've added 5 gals of water to keep levels right, then I do a water change, sometimes the same procedure will take 2 weeks to occur,. Depends on how much water the plants are transpiring. Problem 2. Vertical stems are a genetics and high speed growth acceleration that is inherent in DWC systems.. technique I use involves removing the base fan leaf by bending it down against the lower trunk till it snaps clean off at the base rather than cutting it.. this ensures that when the stem is bent out, there isn't a leverage point occuring against the leaf stem which causes the branch to split as in your pic, (don't worry though, they heal quick). Give it a good week to heal before attempting another bend, and brace the base with your free hands thumb and index finger. Also, allowing them to stretch a bit more first andor bending less and more often over a longer period of time... Happy growing! Keep it Green.

Are you using anything to keep the res bennies happy like hydroguard or z7 ect... The browning could be the start of pythos. If your res temp is above 21°c then you will be bang on the conditions that dwc killer loves !. Keepn the res below 19°c by any means possible. One great way is to cover all your pots with silver bubblewrap insulation. The kind used for roof insulating or wrapping round Jacuzzi's. It is cheap and works amazingly well. ( check my diary of rdwc for example of the pots duringn heatwaves. worked so well !) You also need plenty of micro air bubbles for the bucket to make surface Dissolvable oxygen . The Ph drop is also a part of the plants deposits back into the res during exchanges. Ideally ,starting at 6.2 and slowly dropping is what you want as it allows the full oh range to help release and uptake the elements from nutes . swing is good and also can be a good indicator of how they are actually feeding too if you check ppm as well. I will put a chart on my current grows BlackBerry week 10 pictures to show you the best way to read a dwc feeding and ph swings meanings and fixes. It is a great way to dial in your feeds to the sweet spot every time. Any lockout issues require a flushing of ph'ed water for a day to reset the root access too. Hope the chart on my BlackBerry fast buds week 10 helps. ( doing it now)

I feel like your nutrient amount is weak , you should increase the dosage. The blue dream Matic can be long to flower depending on the phenotype so maybe you'r on a long flowering phenotype The bulbs can be used during 2 or 3 run , after the efficiency is decreasing and you can still grow under it but with a different final result.