PH going in balanced, coming out low

[xXMidasXx]

Hey guys. Back again doing my first indoor grow and I'm super into it I have all the essentials for a healthy environment BUT! things were going really well until the 2 week out sprout had basically stop growing all together. So I figure it much be needing a new home, so I changed it from a seedling cup to a 1/4 gallon pot, raised the light as it seemed maybe too close (I am running a 94w 4 strip two foot t5) and have a 1200w led that I will Daisy chain with the 94w when the plant reaches a good maturity. So I wait a couple days to see any signs of growth and on day two nothing so I look for visible signs.the plant looked dark green leaves and I hadn't really been giving it much other then distilled water so I start thinking maybe she's ready for a meal. So I mix 1ml of both a&b veg formula with about 1ml Cal/mag gave it about 5 cups of water (tested all aspects of water) distilled water is reading a pH of 5.8 and a ppm of 005 I add my feed changes to pH 5.5 and ppm at 199-200. I add a bit of baking soda to the water to bump up ph, bumper it to 6.5-6.7 pH and ppm to 225. So I am pretty happy about my numbers I know I can do better with a kit and I've been waiting on my pH kit from GH for about 2 solid weeks so doing the best I can at the moment

Anyways, with my numbers decent I water and think to myself well how much pH does the run off have? I fill a cup and pull my sticks out to get again a very low pH I believe it is 5.6 or something?!?

So is there a reason someone can explain to me why my pH is going in 6.7 and coming out 5.6?

Thanks a bunch!
Growing these little shits is hard when you actually care about how healthy the plant is.

 

[Chris Scorpio]

Pics help to see how they look

Not a big soil guy so I'm sure more will chime in soon

 

[xXMidasXx]

I'll post pics just a sec

 

[xXMidasXx]

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[Chris Scorpio]

Looks fine

I think a pH drop of about 1.0 is normal, ish

But I'm not sure

 

[Gadfly]

When I used FFOF the runoff ph was always slightly lower than the water added. A full point seems a bit high but not crazy. Definitely keep an eye on it. She does look healthy.

 

[Emilya Green]

Think of soil like a coffee percolator. If the pH didn't change after dropping through all the stuff in the soil, it would be a miracle. But, just like coffee, the strength of the runoff depends on how much runoff you produce.... the first to come out will be very concentrated while the more you pour through, the more you dilute.
So at what point do you ever have an accurate reading of something from the runoff out of soil that means something about anything going on up top? The answer is never.
Measuring runoff pH from a soil grow, specifically a soil grow using synthetic nutes, is a waste of time. The numbers you get are arbitrary and mean nothing.
To do this correctly, simply water every time with the proper pH, ie, 6.3 in soil. When you saturate the soil with this amount of fluid, that column of suspended water, hence your container of soil, is sitting at 6.3 pH. It has no choice. As the soil begins to dry out, top to bottom, the pH of that region drifts toward the dry base pH of the soil. People over think this and then try to adjust to a ghost that they think they see, and a perfectly good grow gets in trouble.