Looks good dude.
Good choice on the fan. I got a 100cfm for same size tent and barely created any negative pressure. I'm planning on getting one of those 49$ units to use as my emergency dehumidifier connected to my humidity sensor.
Only thing I would recommend changing, is the PH Pen. I got one like that and they are not very reliable. When it comes to PH, I highly recommend shelling out a few dollars more to get something that will last a long time.
Here is what I would propose:
Oakton PH1 Tester https://www.amazon.com/Oakton-PH1-Eco-Tester/dp/B01LXTB8SE/ref=sr_1_1?s=lawn-garden&ie=UTF8&qid=1519012426&sr=1-1&keywords=tester+ph1
PH Storage Solution for Sensor Probe https://www.amazon.com/Storage-Solution-Electrodes-Traceable-Reference/dp/B0071AR9XI/ref=sr_1_4?ie=UTF8&qid=1519012478&sr=8-4&keywords=ph+storage+solution
PH 7 Calibration Liquid https://www.amazon.com/General-Hydroponics-7-0-Calibration-Solution/dp/B001D0CKYK/ref=sr_1_3?ie=UTF8&qid=1519012518&sr=8-3&keywords=ph+7+calibration
Also, are you planning on measuring your EC/PPM?