SOIL New Grower May Be In Trouble Need Advice

[TheKieftan]

Ok so I’m on my first attempt growing indoors I only have 1 main plant a week after purchasing I successfully diagnosed and treated a magnesium deficiency with it I’ve now had it for a little over a month this morning I woke to find a familiar yellowing between the veins and quickly gave it cal mag but now I’m thinking it’s a new issue but I’ve done so many things with it recently I’m not sure what could be causing the issues depicted below (I suspect possible overwatering) I’ll list them hopefully you guys can give me some advice 5-6 days ago I transplanted from a 1 to 2 gallon pot It’s the second transplant I’ve done the first went great I moisten the soil with nutrient water using an empty pot to form a slot and just plop the plant into the perfectly formed hole lastnight was its first watering of just plain water after transplanting around 30 oz the 2 gallon pot was feeling nearly dry which is when I like to water before this the plant was looking beautiful I check on it this morning and see the yellowing in between veins associated with mag deficiency and give 16 oz of cal mag water also the temp which is normally between 76-80 spiked the last couple days due to unnatural winter heat it got up to 88 for short periods over the last few days in my tent the way I see it the possible problems are

1. Nutrient toxicity from using ferts when transplanting ( I now hear that’s bad)
2. Over watering
3. Stress from transplanting
4. heat stress

[YYCannabis]

What’s your pH going in and out?

If you’re certain it’s a magnesium issue, it only gets taken up by the roots at a pH of 6.2 or higher. If you keep your pH below 6 constantly, it can cause issues.

edit...never mind my comment. I forgot in soil it takes up at a lower pH range. (I was thinking in terms of hydro numbers)

[TheKieftan]

Yes I believe you were right about the PH sorry for the long reply I’ve been busy and I wanted to investigate this issue thoroughly before responding I believe my mistake was trusting my well water PH would stay the same after nearly a month of testing every single watering or feeding and beginning to run low on PH test solution I for the first and last time trusted my previous experience and added the normal amount of PH down with my luck however it seems the recent surge of rain and snow decided to hit my aquifer at this exact time this diluted the water lowering the PH in the aquifer by .4-.5 a minor change but enough to upset my baby the water I had given her was about 5.75 instead of 6.5-6.25 which I normally aim for it seems I should also apologize for the long winded reply as well lol but I always like to hear how stories end which is happily this time my baby is thriving and just now entering flowering thank you for your advice and happy growing

[Rwise]

5. PH issue
Go to this page and read the details https://www.growweedeasy.com/cannabis-symptoms-pictures you will find that under every deficiency there is a common factor, PH! And with any deficiency PH is the first thing to look at and fix. Sure tossing something at it may help for a bit, but it does not fix the issue at hand and the problem will show up again.
So, whats the soil PH?