Old leaves yellow .. burn or defiency ?

[tantrix]

Strains : Auroa Indica , White Rhino , Strawberry Couch and Super Lemon Haze

What type of medium; Soil

What brand and type of soil? Eco certtified with cow compost and dolomite

How old are the plants? 4 weeks from seed

What type of lights and how many watts? Now 250 w cfl for veg , then 400 + 600 w hps from flowering

How far from the lights? 2 - 4 inches

What is your watering frequency and source of water? Every 3-4 days with good quality tap water thats been stading for some days.

What, how much and when was it fed? NPK? First 3 weeks Biobizz bio heaven and root juice 2-4 ml / L , yesterday biogrow and bioheaven 3 ml / L

What are the temps and humidity in the room? 25 - 29 c , RH ca 40%

Any other pertinent info? Ph tap water is 8.0. Ph in soil / water is 7.0


Pictures is from the day after watering with biogrow 3 ml / L for the first time. Prior to this they was feed with root juice and bio heaven.

The white rhino had the old leaves yellowing and chlorosis more than a week ago , but it got worse the last few days. Now all plants show signs of yellowing and some cholorosis and some also brown leaf tips.

Is this more developed defiency , or may the plants be burned on one nutrient and still deficient on other after the watering with biogrow / bioheaven yesterday ?

The soil already getting dry only one day after watering.
I filled the soil ligtly in pots and got leca pellets in the bottom 2 inches , can the issues be caused by to good drainage when watering ?

White Rhino is worst affected , chlorosis and yellow leaves for more than one week Last day some of older leaves turning yellow enrierly and some leaf tips are brow.

The Aurora Indica got more yellow leaves and brown leaf tips the last 2 days.

One of Strawberry Cough got yellow and brown leaf tips the last few days

Other Strawberry Cough leaf tips and edges got brown the last few days.

Super Lemon Haze is lest affected but some the leaves curled a little after the last watering.

 

[Vash]

That first pic looks like a magnesium deficiency. Go look in the "...sick plants.." thread and you'll find a pic very similar to what you have. Are you growing organic? That looks like an organic medium, but I'm confused on what you're feeding them. Is that organic nutrients?

 

[L~B]

It looks to me me like your soil might be a bit hot and or your over watering. If look at edges of your leaves there clawing like going up making the leaf like a bowl sort of. The plant dose this when it can't dissipate h20 this can also be caused by toxic salt build up and soil being too hot.So if the pots are still heavy don't water...Until you get it sorted I would hold back on nutes.

 

[Mr. Greengenes]

Like L~B, I'm thinking watering. You don't say what size pots, and I can't tell from the pictures, but you mention that they dry out in one day. Overwatering and underwatering often follow each other. Only a few hours past dry is enough to start losing roots. Then, when the plant is finally watered, the lack of (living) roots in the lower part of the mix results in overwatering. Watering issues often show up as nutrient deficiencies, and are consequently misdiagnosed. BTW, if the plants are drying out in one day, it's time for a repot.

 

[Hazy Lady]

I'm with Vash, it's Mag def, but you still need to find what caused it, not enough Mag in your diet, PH issue causing lock-out, etc etc.
I would also second what Mr Greengenes says too, if its dry daily you need to re-pot.