Nute burn from watering or something more sinister?

[Waira]

Thanks Waira, there has been no spreading of the whitish tips from the first photo, so that seems to be ok. The other lady has been ok (although I had a worry about her going all droopy yesterday. As a newbie I instantly panicked and posted that on here too lol, but she’s back to her perky self today).

You must hate newbies like me, worrying over minor things! At least I now know for my next grow that I need to step back and not over react to every little thing!!

:smoking: nothing doing mate, that's why AFN is the best! Sick Bay especially is a "safe place", I tolerate ZERO dickheads, know-nothing blabbers, spin-the-wheel guessing, etc.,... Peep's need to be able to come here with no worries about ridicule or lousy advise.... And I'm stoked you were observant enough to spot something and get on it right away!
Have a look in the Reference section for lots of good info, and the Defc. Pic Depot as well where you can see and learn more about defc./toxocity symptoms, how they are often tied together, and how pH governs everything!

Theres no better place to learn than in the infirmary! I've only just got my 2nd ever crop drying (total noob) but I spend so much time reading these posts that I'm fully prepped for issues I'll probably never even see!

You keep asking, the resident doctors keep diagnosing and I'll keep learning. Wins all round!

always learning...

Cheers HJ, I was going to bring that up too,... diagnostics is not easy at all, so much is tied together, interelated, it's a huge subject to delve into... but a little basic research and learning can help you spot trouble sooner, and maybe even figure out what to do about it... learning from others mistakes is allowed-

to do this well, and let prevention be the best tool to use, you'll need the right tools for the job! ...missing critical info will leave you guessing at best
--TDS/EC meter: test water hardness, nute solution actual concentration, run-off ppm's

-- pH meter (liquid only): spend the $ on a decent one, and make sure to take proper care of it, they are easily f'ed up... storage solution, calibration solution 7.0 and 4.0, rinse rinse rinse with pure water (RO/Di) between each use...
-- for soil/soilless media (coco, Promix et al), measuring in-pot pH is the real key, and you need a pH probe (wrongly called a meter sometimes)... Control Wizard Accurate 8 (or identical unit, different brand name) is a nice lower cost option; had mine for 5 years, still does the job well enough! Blue Labs make a more "Pro" model, works like a pH meter (electrode bulb), but $$...
Run-off testing is not a good measure, for many reasons, let's leave it at that... It can serve in a real pinch, and only if done right otherwise you get badly skewed results that are of little help...
By dialing in your inputs pH beforehand (always add Ca-Mg first, BTW), you take the burden off the medium to do this which in some cases it can't,... pH in=pot is very dynamic, so many sources of influence going on in there! It'll stay more stable, and in-pot testing will help you spot shit going sideways before it badly impacts the plants!