Browning fan leaves - First timer

[MrRudeic]

My lower fan leaves are browning, and i wanted to know if i was burning them, cal/mag deficiency, or just normal fan leave mortality? Am i over worried?

Hybrid autoflower
Blue by pryamid seeds
5 plants (3of5)
Soil: 33% fox farm Happy frog, 33% perlitre 33% sphagnum moss
3 gallon Smart Pots
PH 6.5
300 watt led
45 watt led
80 cfl
Time 3 weeks vegetative
5x5x7ft grow tent
Temp 79-81
no pest
Watering every 4to5 days
Fertilizer: Old Age growth 1/4 strength and cal/mag 1/2 strength every other feed , but only fertilized twice
Hum 40% to 54%

Thanks for the help in advance.

 

[Stoned Redneck]

There is always some leaves that die or wilt.Just keep an eye on the new growth, If that looks bad ,Worry ! Some older leaves acting up? bound to happen somewhere,Red Or its just the cigarettes.... haha

 

[Atulip]

Looks like phosphorus deficiency. If you're 3 weeks into veg you should be closer to full strength nutes. Up them to 1/2 or 3/4 and see how they respond.

There is always some leaves that die or wilt.Just keep an eye on the new growth, If that looks bad ,Worry ! Some older leaves acting up? bound to happen somewhere,Red Or its just the cigarettes.... haha

Older growth shows deficiencies first on mobile nutrients(n, p, k, ca, mg) as the new growth starts robbing the older leaves of their stored nutes. Growth typically slows or stops until it's corrected. The exception being N deficiency in mid/late flower.