I am growing autos for the first time, one is an auto #1 plant, im using 400w hps, its in its forth week and im using fox farm trio nutes. in the third or so week I noticed yellow tips on the plant that looked like nute burn but I was using minimal nutes, ive tried to get it right but now the leaves are clawing, yellowing and feel slightly crisp. it seems to be getting worse and I know it must be a deficiency but not sure what to do, someone please give some advice, it is starting to flower and doesn't seem to be coming along in a healthy way. im worried its gonna flat line. ill post pics if no one is sure what im seeing. please help, thanks