My first [recent] hydroponic grow.

The pineapple auto flower was germinated at the same time as the blueberry. It took some time to catch up, I'm not sure what I did wrong but it's just now starting to show signs of future success. I had a couple other auto strains that all failed to sprout due to my negligence. Update on those, my last seeds seem to have taken when I opten to put them in my outdoor hydro setup for germination. The conditions must be better with the uv from the sun preventing over dampening from being a molds paradise. I don't have the time to watch these all day so this was my best shot. I noticed some yellowing. Turns out my ph was off because I never calibrated my ph sensor. Fixed everything 10-Jul, hopefully she comes back to vitality soon or the yellow is just light green from the new leaves.. I diluted the nutrient solution down today but only to 1000 from being up to 1200. If nothing changes in a few days I will replace half the current reservoir supply with new ph adjusted water. I don't dechlorinate with a filter but I bubble the water for a day and hit it with uv just for good measure before adding new water. Update, after researching, it appears this is iron deficiency. Hopefully correcting the ph is enough to prevent the yellowing from continuing. Fingers crossed. Else I need a supplement. Update July 11, after calibrating my ph monitor and getting back in acceptable range yesterday [I have been shooting for 6.0 or just below] the leaves are becoming more dark green in color and the yellowish color is dissipating. You can see some of the lower leaves have some sort of burn. I am not sure if it is heat damage or caused by ph imbalance but I don't see this on the newer growth.