Im new to this, im sure you can tell my crop has got the yellows and I am a bit stumped, ph looks ok, tried backing off water and using fish emulsion to fertilize. Using 400w HPS, looks like N deficiency but ??? Any thoughts Thanks CH
Not pH, it's definately either nitrogen of magnesium. Try to get a picture of the affected leaves that's a little closer. It's either N of Mg though.
Also it's obvious you need more light. To grow weed properly, you need 6,000 lumens per sq/ft. Judging from the sparse growth, I'd say you're working with far less than that. In fact, unless you get more lights, I'd be surprized if you get any bud at all. And use a full-spectrum nutrient. Fish emulsion is great for outdoors, not so good inside.
Sure looks like N migration to me, CH. Especially since it's the lowest/oldest leaves on the plant, which is where it tends to start. Nothing to get really freaked over, but if you're still on a lower level feeding regimen, you might wanna bump it up a bit. Doesn't look like your leaves are "praying" for Mg, but a pic from higher up on the plant would say a bit better. Since you've checked your pH level (and I assume it's in satisfactory range), I'll figure that what looks like streaking on the leaves (to me) is actually where the leaves have gone necrotic, and not due from P lock out. I agree with RD, your internode length looks a lil' stretchy there. Ya might want to whale on 'em with some brighter or supplemental lighting. I haven't had a grow yet where the plants at some point didn't have some N migration...some strains a lot more than others. Just mind your food levels, adjusting when necessary, and leave the yellowing leaves on until they fall off on their own, or you absolutely can't stand to see 'em anymore. They'll continue to act as N reservoirs for your babies. Sorry, I've no idea what plant nutes are available down under...but religiously avoid anything for lawns, ornamentals and such, and try to find a hydro shop or nursery with something for "food grade" crops.
Thanks for all your help, yes it was definitely N def, feeding increased N and plants are going ballistic Cheers
