single blade leaves dying on 1-1/2 week old plants. is this alright?

This is my First time growing from seed. The lowest set of leaves, the single blade ones, have started to go pale and get brown spots on them. I researched as best i could and found its normal for the cotyledons to start dying, but these ones aren't the cotyledon leaves are they? also, as visible in the pictures, the 3 blade leaves are turned down at the end. im growing in coco, watering every 2 days or so. i add about 1-1.5 ml of cal-mag to 2L of water (obviously im not giving the tiny plant the whole 2L, i use it through the week, pour whats left away at the end of the week and mix a fresh batch). is it phosphorus deficiency? is it meant to happen?
i've also noticed the newest, tiny growing leaves in the centre have a sort of purple area on them, i'm not sure if it can be seen in the photos.

also, on a slightly related note, when do i start adding canna a and b. should i be doing that now since the coco is inert? does it have phosphorus in?

these leaves are clearly done for, but is the plant boned as well?

Hello Jazz,

Yellowing from bottom Usually is a sign of Macro nutrient deficiency. The plant is diverting it's resources to new growth. They look like maybe they could do with a feed. I have not grown hydro in years so forgive me for not knowing your exact feeding schedule. try to give them a weak nutrient solution feed. Do not over do it though. less is better than more when they are young.

Cheers,
Will

Will Thayer said:

Macro nutrient deficiency

Click to expand...

yeah, i've been thinking its a nitrogen deficiency, maybe phosphorus as well. i'll start adding the canna a and b to my water because im pretty sure it has nitrogen and phosphorus in, i cant find an N-P-K ratio for it though (they're in oasis bottles because i got the nutes from a friend so it doesnt have a label i can read) ill add like a 1.5ML per 2L of water each like the cal-mag so i dont over do it. ill do it in a day or two because i watered it earlier today with just cal-mag and i dont want to drown it.

Thanks will.

Hello Jazz,
Perhaps this will help you out. Canna grow schedule
I look forward to watching your progress and good luck

Cheers,
Will

yup, this is really elucidating how i cocked up. should have been using A and B from the start.

thanks again will, bloody lifesaver

Hey Buddy,
The more ya grow, the more ya know. Things are going to turn out just fine for you.

Cheers,Will