PPM or pH?

So I am just trying to understand which numbers i should focus on. I am using Fox Farm line up for the fertilizer. I started mixing up the big bloom for my seedlings (I am just barely seeing my second set). I started to mess around with the pH and after I got it to a pretty good color I tested the water at 960PPM. Which is high according to the feeding chart. Advice?

Any takes on the fox farm granules fertilizer? This is my first grow as I stated before so I don’t know if I should go ahead and rock with the line up or should i just stick to the trio and get a feel. I have one small tent 224.

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Ph and PPM are more worrisome for hydro than dirt growing. Either way it is something you want to monitor. The more nutrients you use, the more it usually lowers your pH. 960 is way too high for seedlings. You should be down under 300 to get started with a pH between 6 and 6.5, regardless of what the feeding chart says. Growing with organic nutes I still wouldn’t be up over 300ppm until after week 4. If you’re growing in dirt then you shouldn’t start fertilizing until at least week 3. For the first 2 weeks of a seedlings life it’s receiving it’s nutrients from the seed so feeding is just a waste of your fertz. I usually start with just worm casting juice or kelp meal and water. By week 4 I’m usually transplanting into the final grow system, be it dirt or hydro, and that medium is full of all kinds of goodness. So if you’re doing something similar, your plants will be fine. After the transplant is the right time to up your nutrients but your first couple feedings should just be good old H2O because the soil is going to have plenty of nutrients to feed. Since this is your first grow I’m recommending these things. Once you’ve learned how to read your plants and know how they’re responding to different lighting or feeding regimens, you’ll be able to make judgement calls based on your experience. As far as Fox Farm goes… You’re going to pay up for the name. But that’s how most of us got started because the stuff works good. Big Bloom is designed more for flowering and not vegetation. You can tell from the name and the NPK. You need a higher nitrogen concentration for bigger veg. The Grow Big is what you’re going to need for solid vegetative growth.



PH tells you what nutrients your plant is able to access from your medium.

PPMs tell you how much your plants are “eating” and how much they’re leaving in the medium.

You need both numbers to properly care for your plants, especially with Fox Farms. Definitely follow their scheduled flushes, too.