First time grower - Anyone know the issue?

[hhw01]

Hi everyone,

I have noticed an issue on some of the leaves of my plants. Any help identifying the issue would be great.

Growing in Plant Magic Supreme - seedlings were planted in jiffy pellets then planted into the final pots.
Have been using Mills A & B - no other nutes so far. Have given them a plain water feed today and then the previous two feed were 1ml of A&B per plant. No other nutes have been fed apart from this.
The plants are Northern Lights Autos from Sensi Seeds and they're about 20 days old.
Temps are 25-30 degrees
Humidity 45-50%

 

[namvet25]

What is the NPK mumber of your nutes? and the 1 ml feed is that per gallon or litre? Make sure your entire pot is moist.

 

[hhw01]

What is the NPK mumber of your nutes? and the 1 ml feed is that per gallon or litre? Make sure your entire pot is moist.

The 'A' is 4-0-1
The 'B' is 0-4-3

and the 1ml feed is per L

Thanks for the help

 

[namvet25]

Start using cal/mag if you can find it.Your dosage sounds ok but only feed twice a month.