Please help confirm diagnosis.. Mg and N??

G’Day,

I was just wondering if I could get some help with this. I’m a first time grower so it’s more about the learning then the end result, but I’ve had a go at diagnosing these plants and I just can’t seem to nail it. I’ll think its one thing, try to fix it.. then make things worse but live and learn i guess.. anyways.. i was just wondering if i could get a little help diagnosing my 2 little plants.

Now i think they’re technically still seedlings, i’ve seed no alternating nodes and no rapid growth, but i think they’re not far off it.. if they can get better! I’m growing under a 250w HPS in soil. Soil is a mix of some plain organic soil, compost, lime and perlite. PH for the soil is sitting on 7. The cab temp sits at around 87F which i know is high, i’ve got some things on the way to hopefully help lower the temp. At the moment I’m water every 2-3 days. And every 3 waterings with a really light fert of fish emulsion, because of the problems i’ve been having with these plants i thought best to dial down the ferts heaps and to eliminate over ferting from the possible causes. Strain is unknown, they’re just some seeds i was given.

Now the plants.
Plant 1 - From the research i’ve done i’m guessing this is a magnesium deficiancy??


Plant 2 - Is this an N deficiancy?


On the plus side, I think plant 1 has shown me some pre-flowers.. and it’s looking good!!


Thanks in advance for any help/advice.

Flush and get the PH down a bit. Could be Mg def. When mine were a couple months ago, it started out as yellow spots on lower leaves and then moved to brown larger spots. To me it looks like a couple of different problems. So i would probably flush and try to bring down your ph about half a point and then hit it with a good 1/2 strength dose of good nutes like big bloom or something with a wide variety of usuable nutrients and trace minerals. good luck man

Nope. That is nutrient burn, nutrient toxicity, salt build up.

You need to flush that soil, you've been over feeding so you'll need to address that behavior too. If you haven't been over feeding then your soil has too much food in it. Either way, flush, flush, flush.

couple of different replies.. thanks heaps.. would appreciate abit more input though to make a final decision.. i guess until then i should be flushing..