Two different plant issues, please advise

This is week 2 for my babies and they are getting 1/4 strength advanced nutrients micro, grow, bloom. The bigger healthier plant is getting brownish on the tips of the leaves. The other plant is yellowing completely. Anyone have any advice?


Temps are in the mid 80s, water temps at mid 60s. The large plant has lots of root mass growing in the water. The others do not. View attachment 1003188View attachment 1003189

I use RO water and AN claims to be pH neutral. 400w hps in a grow tent that remains open

are you not adjusting the ph? My RO water is close to 8.0, you need to test it and check after nutes are added. I take it you are growing hydro as you mention water temps, than the PH should be 5.5 to 6.0. i usually shoot for 5.6 if it's the the first time i am refilling the reservoir. After that I try to keep it at 5.8. Good luck and let us know how it turn out...JR

I feel like a dumbass. I hadn't checked my RO water, because I figured it was 7 pH. I'll get a meter ASAP

http://www.amazon.com/pH-control-kit-General-Hydroponics/dp/B000BNKWZY/ref=sr_1_1?ie=UTF8&s=home-garden&qid=1277157409&sr=1-1

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