Is this just fading or is it a deficiency?

[Oldhat]

Problem: rust coloured tips and fading leaves

Medium/grow method: soil

Feed: and supplements used: big bud organic half strength, also use magnesium sulphate mixed into water once every two week and the soil was amended with dolomitic lime.

water source: tap ph 6.5-7 runoff 6-6.5

Strain/age: crop king trainwreck auto
59 days from germination roughly 38 in flower
light used:400watt hid about 18-20 inches from canopy

Climate: 20-28c 45-55 rh

Additional info: the seed packaging says 8 week flowering period.

 

[namvet25]

What is the npk value of your nutrients?

 

[Oldhat]

What is the npk value of your nutrients?

1-2-5

 

[namvet25]

That is really low in nitrogen which may cause leaves to turn a lighter green but they look fine right now but if they keep on getting lighter green try adding a little nitrogen or veg nutes for one feeding.

 

[Oldhat]

That is really low in nitrogen which may cause leaves to turn a lighter green but they look fine right now but if they keep on getting lighter green try adding a little nitrogen or veg nutes for one feeding.

Thanks. I am not using any nutrients other than the big bud. It’s all organic soil. I’ll top dress with some worm castings and give them some worm casting tea.

 

[Waira]

Hmmm, hard to believe this is nute burn, given all that,... I see some margin "teeth" browning along with the tips too, which is usually K defc.... but then i see most all the tips are burned? ...strange,... how much epsoms are going in, and how often? I'm wondering if some salts build-up may be happening here,... BB alone isn't the best NPK balance either, it's meant to be used with the base nutes as well, balancing things out more,... I think more P is needed during bloom, but no signs of defc. though- .... plant is oddly deep green, usually a high N symptom

 

[Oldhat]

Hmmm, hard to believe this is nute burn, given all that,... I see some margin "teeth" browning along with the tips too, which is usually K defc.... but then i see most all the tips are burned? ...strange,... how much epsoms are going in, and how often? I'm wondering if some salts build-up may be happening here,... BB alone isn't the best NPK balance either, it's meant to be used with the base nutes as well, balancing things out more,... I think more P is needed during bloom, but no signs of defc. though- .... plant is oddly deep green, usually a high N symptom

I talked to the local hydroponic shop owner yesterday. He figured the burn was from the light being to close. The bulb is new and I moved it up about four inches. I am only giving them the magnesium sulphate solution once every two weeks and it’s a half strength mixture 1/2 tablespoon per gallon of water and only using 250 ml of the solution for each plant. Other than the leaf tips browning and some of the leaves going light green the plants are doing well. Thanks for taking the time to reply.