The initial addition of say, citric acid, will drop the pH – generating citrate ions in the process these will then be absorbed by microbes and plants, increasing the pH again rapidly. Good but not ideal.
Had a peek at diary and I will do my best to give you a idea of what I think is going on based on what I see. I'm not always correct so take what you will with a pinch of salt.
Your ph was last week up at 7.7, now it sits.7.0 which is fine ok, ph can tell alot of what the medium is composed of.
Closer you are to ph of 7 the higher saturation level of the big 3 cations. What are the big 3 cations? Potassium (K+), magnesium (Mg2+), and calcium (Ca2+).
At ph 7.0 100% base saturation.
Do not add anymore Ca Mg or K. Your massive spike to 7.7 tells me you just keep filling the soil with more and more cations, you do not need. Either that a response from the citric acid.
As a cannabis plant grows the medium naturally acidifiys as reactions happen, over time ph will slide down once it gets to around 6.2 I'll reapply more cal mag boosting back to 6.8 or thereabouts.
Soon as you go over ph of 7 micronutrient uptake will begin to be effected , lime greening occurs alongside with whatever nutrients were already beginning to run low, this can present as multiple symptoms, if the plumbing is messed up nothing moves.
I dont see any dmg to the leaf tips from osmosis so your mediums salt content (ec) is still in a decent range, this is more a excess causing a disruption of the ratio.
The three primary plant nutrient cations, potassium (K+), magnesium (Mg2+), and calcium (Ca2+), can exhibit antagonistic effects on each other, meaning that an excess of one can negatively impact the uptake or availability of the others. This competition arises because they share similar transport pathways and binding sites within the plant.
Plant is drooping, means water is not moving like it should, your running 81f and 45% not optimal for vpd but perfect for encouraging gas exchange,
Potassium is a key player in maintaining proper turgor pressure, which is vital for various plant processes, including growth, water regulation, and stress tolerance. Possible the drooping is from a antagonistic effect of calcium and magnesium disrupting pottasium from uptaking at all.
Potassium, calcium, and magnesium are all positively charged ions (cations), and they share similar transport pathways in plant cells.
High concentrations of Ca and Mg can compete with K for binding sites on these transport proteins, reducing the overall uptake of K.
Hope that helps with your understanding of the problems you see. 🙂 best of luck with your wee plants.
6.2 -6.8 ph
0.3-1.8 ec
If you control both of these, and you understand the water cycle, then you know 100% what you see is symptomatic of a deficiency or toxicity of nutrients. Either through actual deficiency or a breakdown in the SPAC waterworks.
The Soil-Plant-Atmosphere Continuum (SPAC) refers to the continuous pathway through which water moves from soil to plants and eventually to the atmosphere. It's a crucial concept in understanding plant physiology, hydrology, and agriculture.
Gluck
