Slight N toxicity. Flush or ride it out?

[Benjidubwise]

Your fluctuations are a bit much. 15f+ degree temp swings invite mold and pathogens. The swings in temp can affect nutrient and water uptake that can appear as a myriad of other problems. I like to keep numbers close, 77f-86f and ideally maintaining humidity within a 10% range, 40-50/60-70/etc. Plus nitrogen issues begin at the bottom of the plant, that upper clawing looks like environmental stress. I think your environment is more of an issue here but the I'm not seeing a real issue

Apera instruments makes some nice handheld meters. I have the 5 in 1 that measures EC/PH/TEMP and some other stuff but that's it. 7.5 pH water is actually quite nice, mine is 7.3 from the tap and if I remember correctly good drinking water is right around 7. The one below is inexpensive compared to $130 for the Apera

HAPHID Combo Meter Professional Water Quality Tester High Accuracy 4 in 1 PH/TDS/EC/Temp Digital Multi-Parameter Tester for Laboratory,Aquariums, Hydroponics Pool,Spa,Drinking Water and More Amazon product


The other thing is aerating your water will make your pH rise unless your nutrient line is stable. Everything I've used besides Mega Crop fluctuates hard and aeration isn't really needed outside of DWC. I run a 55 gallon res that isn't aerated and the ph takes weeks to drift.

I know the environmentals aren't ideal but I just don't have the spare cash to throw at tightening everything up at the moment. It's not daily that they're having such extreme fluctuations, just when we have an extra warm/cold day outside. New ph pen arrives today

 

[Death The Cultivator]

I know the environmentals aren't ideal but I just don't have the spare cash to throw at tightening everything up at the moment. It's not daily that they're having such extreme fluctuations, just when we have an extra warm/cold day outside. New ph pen arrives today

I completely understand, it's taken me three years to get most of what I have and some of it was second hand. If you can't entirely control the environment then you just have to be proactive about other things.

Micro climates can harbor insects and mold with inadequate air flow plus stronger air flow can lower the leaf temperature between 1-5f lower than the ambient temps. If it's dry, water more to avoid stressing the plant, mist the leaves if you need to. Too cold use a heater, but keep everything clean and add on as you can.

 

[Benjidubwise]

Hydroponic mediums, DWC or coco flush and reset would be the answer. In soil, you can't flush out the nutrients. Get a pH pen that'll work for you, plain pHd water, a little calmg... and ride it out.

@Arthur there's something I've never understood about not being able to flush in soil.. I'm sure it's my ignorance but the same question always pops into my head. If you accidentally fed with 10x more of "nutrient A" then the water in the soil would be heavily concentrated with nutrients. If you then watered with clean water, surely at the very least the fresh water would massively dilute the overly enriched water that the roots were already sat in, if not replace it entirely??

 

[Arthur]

It's not the nutrients your adding that you can't flush, it's the overly hot soil that you can't reduce. Bat guano is high in nitrogen, you can't wash the soil out of the soil...
Not to mention think of a coffee filter, yeah you'll get some out the bottom, but the grounds are stuck due to soil being much more dense than coco.