Magnesium deficiency?

My last 3 grows have had same issue as this one. Rust spots appear on lower leaves and upper leaves are light in middle and darker on edges.
I thought it was my very hard water in previous grows causing magnesium lockout so I switched to bottled water. 150ish ppm compared to my 400ish ppm tap water. was in soil before with gaia green nutrients, now in only plain promix with green planet's medi one nutrients.
nutrient solution is ph'd to 6.4 when fed.
only began to notice the issue yesterday morning.
If I move to RO water, what might an adequate amount of calcium be to look for in my nutrients so I know I dont need to add extra?
any ideas?
Thank you!

your new growth has a lot of tip burn

rkymtnman said:

your new growth has a lot of tip burn

Click to expand...

well, I guess its feed, water, water then from now on....
I've been doing feed, water, feed at about 1/3 recommended solution strength.
But, can this be my only issue, overfeeding possibly? I thought I was going too easy on the feed this round.

LordEnki said:

My last 3 grows have had same issue as this one. Rust spots appear on lower leaves and upper leaves are light in middle and darker on edges.
I thought it was my very hard water in previous grows causing magnesium lockout so I switched to bottled water. 150ish ppm compared to my 400ish ppm tap water. was in soil before with gaia green nutrients, now in only plain promix with green planet's medi one nutrients.
nutrient solution is ph'd to 6.4 when fed.
only began to notice the issue yesterday morning.
If I move to RO water, what might an adequate amount of calcium be to look for in my nutrients so I know I dont need to add extra?
any ideas?
Thank you!

View attachment 5167479View attachment 5167480

Click to expand...

Looks over watered. What EC are you feeding at ? What lights do you have and how close are they?

twentyeight.threefive said:

Looks over watered. What EC are you feeding at ? What lights do you have and how close are they?

Click to expand...

They could be over watered, possibly. they've been quite light after 2.5 ish days and thats when I water. top 1.5 inches of medium is very dry when I water.
I haven't checked the ec... I'll check next feed. I've been feeding at .25ml/L when the recommended amount is 1ml/L.
480W LED. dimmed to 220W @ 20 inches
They're in 1 gal pots, watered with 500ml

Thanks

Over watered or not a good frequency.

keep it real. said:

Over watered or not a good frequency.

Click to expand...

well, it would have to be over watered if its between those two... my previous grows failed due to my lazy watering habits. I'm on-top of watering these days...
But, I am going to let them dry out an extra bit longer before I water again.
Maybe the water I'm using this time is still too high in calcium in addition to the .95% already in the nutrient solution?

twentyeight.threefive said:

... What EC are you feeding at ?

Click to expand...

Does my reading of 424 uS/cm equal .4 EC? If so, that's only my water, pre nutrients.

still sliding downhill...

transplanted both into new medium. we shall see how this goes...

Seem to have recovered since transplant...

yeah those pots were becoming too small maybe - check your ph meter as well, are you still in soil?

yosim said:

yeah those pots were becoming too small maybe - check your ph meter as well, are you still in soil?

Click to expand...

yes, it's possible the pots were getting too small. I never actually pin-pointed my issue. The transplant seemed to help, though.
I wasn't in soil to start, only plain promix out of the bag. I transplanted into Black Swallow living soil.
I'm looking into a new PH pen, but I do have strips and a shitty pen if needed.

LordEnki said:

yes, it's possible the pots were getting too small. I never actually pin-pointed my issue. The transplant seemed to help, though.
I wasn't in soil to start, only plain promix out of the bag. I transplanted into Black Swallow living soil.
I'm looking into a new PH pen, but I do have strips and a shitty pen if needed.

Click to expand...

Make a berm around the stem with new dirt,this way when you water some nutrients get washed down into the original root ball.

myke said:

Make a berm around the stem with new dirt,this way when you water some nutrients get washed down into the original root ball.

Click to expand...

thanks for the heads-up.
ill spread a bit of EWC as well

12ish days after transplant, the plant in 5 gal is showing same symptoms again.
They were both transplanted into fresh living soil from Black Swallow... their KIS mix.
Can it be PH problem? both are getting same water....

Kind of looks like mag def or iron def.
Check this out

Bummer,well you'd think the soil is good for pH.Your water is bottled right?

What about light,I assume you pulled it back?

Im stumped ,fresh dirt should be happy as all get out.

LordEnki said:

transplanted both into new medium. we shall see how this goes...


View attachment 5172702

Click to expand...

Epsom salts in water, mist down a few as and they will green right up. My tap water 450ppm mostly calcium, l add 50 to 75ppm and up to 150ppms Epsom salt to res every watering. Leds make them use more cal so need mag to offset it. Less is always more is a good rule. Can always stop using anytime you want, l buy the big bag! Poor man's calmag! Black Swallow is a few blocks from me. Buy most add ons from them! Ewc etc.

rkymtnman said:

your new growth has a lot of tip burn

Click to expand...

What size tent is that