I have 4 8 gallon buckets using the real CC undercurrent system and Im in the begining of flowering. Im not due for a complete flush for a week but Im a little concerened about my ppm numbers. I started off on the last flush @ 600 plus ppm using and RO system, and I use calmag to ccompinsate. My newly flowering plants are sucking up 5 gallons of water every 2-3 days. I just added 5 gallons to the sytem and my ppms are 450 or so which is very low compared to canna's grow guide. I plan on doing a full flush in a week. Should I add anything? Every thing is growing perfect. I got 12 plants growing and im using about 1,500 watts of hps in a 4x4x8 tent. Ph is 5.7 water temps are averaging 73f, remember im on a 12/12 cycle. ai never see the water get above 75f. Here are some pics. I could use some advice.