Does ppm really matter... This is y I ask

I'm 3 weeks in bloom, I'm using advanced a + b, nirvana, bigbud, sensizym, b-52, and calmag. Everything at about 50% and my ppm is still at about 600-700 ( im in RO water) do/should I push it to the around 1k I'm suppose to be at? Is that te benefit to using RO water? Insight please

All PPM is parts per million. The number of some kind of material measured expressed in parts per million.

1 tsp of X put into water equates to PPM of X in your water. Thats all it is. If your growing in soil it really doesnt matter and the unit of measure is usually tablespoons/teaspoons or mililiters.

If your growing in Hydro and say your water with nothing has a 100 ppm and 2 tablespoons of X give you a PPM of 600. Then that application of X in that volume of water is 500 ppm or 2 tablespoons. Since water levels can vary PPM is a much more accurate expression of how many nutes your giving your plant. More water would dullite your nutes and youd get a different PPM. Less water your PPM would increase.

In soil the only PPM you can measure is what you give it before hand. You can use that to track how much you give weekly if thats easier since a TDS/EC pen is pretty cheap.

For myself I just have written what my max mililiter per liter is and remember what I gave last nuteing.

Edited by rhapsodyrcks, 29 August 2012 - 03:00 AM.

As for RO water some use it some use Tap. Ive never used anything but Tap and works just fine.

K, I am in soil, so should I just do away with the whole ppm thing? I really feel like I'm underfeeding sum times in fear of burning them. I'm at about 40% 3weeks in and at times feeding every 9 days ( feed water wate, feed etc) can I increased it a little?

If your at 3 weeks and doing 40% of of the max recommended then your fine. Nutes should not be viewed more is better. Sometimes 40% is all you can do. The OG Kush I am doing can only take 50% about of max recommended amount and there growing just fine. You really should not feed more then once a week as well about.