I'm using roots organic soil. Am I mixing these nutrients wrong or is it normal for the ph to drop after mixing. The ph before I mixed was 6.7
It depends on everything you use. I think it's more common for nutrient solutions to be acidic. But, I recently stopped using calmag and my final nutrient solution is a full ph point higher.
I was using RO water because my tap water ppm is >600. I used calmag to replace the trace minerals in the water. I only used 2-5ml. I started mixing 1:3 tap and RO water to get a starting ppm of 150-200. With that ppm, no need for calmag (maybe there never was). Suddenly, there was no need to use ph up anymore.
More than a few people say there's no need to ph what you pour into soil. But, that probably depends on how much dolomite is in your soil, and how close your nutrient solution is to 6.5. For me, it was 5.8-6.0. Now it's 6.8-7.2. I'd feel ok about using either of those in soil. But, your 5.0 is pretty far out there. If you did that repeatedly I think it would pull the soil ph lower. But, just once should be ok.
Anyway, I assume you're a new grower. After you get some successful grows, play around with other nutrients. You should be able to get your ph closer to 6.5 without using ph-up/down. (
I use Grow More Sea Grow, an inexpensive dry fertilizer made for soil, has organic sources as well as synthetic.).
Before Sea Grow, I used GH Flora 3-part. It worked well. It's made for hydro, not soil. It worked well for me. It was more immediate. I felt I was in direct control of what the plant received. As a new grower that seemed like a positive. But, now I like using a soil fertilizer that relies more on a soil biology to contribute to the availability of nutrients, breaking them down, slower acting, participating with the plant, letting the plant take what it needs. I (and friends) noticed a definite taste difference. Less sharp/harsh. More rich/smooth.
When using GH Flora 3-part I used the
so-called "useless" schedule. That might be something to try. From my experience, it was right at the boundary of what the plants could take. I got a little burnt tips a couple times, a little N toxicity. Not a lot, just so much as being right at the boundary.
When I changed to Sea Grow
I made a spreadsheet to see what I had been feeding with GH/useless. You might want to play with that. You can plug everything with a nutrient value into that spreadsheet and see the actual NPK ratio and PPM strength. Eliminates the mystery of GH's "1-2-3" color-coded bottles. Makes it easy to assess other products to feed the same thing. Makes it easy to get out of GH and into a soil fertilizer.