Yellow spots on leaves

Help for sick or damaged marijuana plants. Marijuana growing pests, diseases, nutrient problems.
Yellow spots on leaves
I am new to growing and have some plants a friend gave to me. They are still in Veg state under 600W lamp. They are about 6 weeks old (I think). The room is at 75 degrees. I have to water about once every 5 days. There is a fan and air filter/purifier in the room. The pH level is at around 7-8. The pH meter is a little crude though.

I use Rhizotonic and Bio Vega (Canna products) as recommended by my friend. I apply the recommended amounts per instructions. I allow the water temp to aclimatize also.

I have yellow spots on the leaves as shown. Some of the tips are curling downward also. Would appreciate some advice here.

Yellow spots on leaves
What medium are you using? Bio Terra plus? Its my understanding that with that line of soil and nutes there is no need to worry about ph, the nutrients are mineral based and available directly to the plant at all ph levels. So I doubt its a ph issue. How big are the plants physically? Can you get us a shot of the entire plant? It could be that the plants are still fairly immature and your your getting some nutrient burn. What kind of air exchange do you have set up? If theres not enough air exchange its possible to get some burn like that. Thirdly and the most likely IMO 5 days seems a little long in between watering unless the plants are small and immature, how are you deciding when its time to water? Best gauge Ive found is to take your finger stick it and inch down if its dry its time to water if its wet leave it be. Best of luck too you.
Yellow spots on leaves
Looks like splash-burn...
are you moving or turning OFF the lights when you spray?

If not-- each drop of water/solution on the leaf acts like a little magnifying glass and burns a nice round spot on the leaf till it dries.
No need for revenge, just sit back and wait.
Those who have hurt you will screw eventually themselves; and if you are lucky, God will let you watch!

Through What we create- we are immortal.
Yellow spots on leaves
i was just thinking the same as Lady Zandra
Yellow spots on leaves
I'm having the same problem, although mine isn't splash burn cause I haven't sprayed my ladies with anything. But the day before yesterday I started feeding them nutrients. I waited 3 weeks though, and I also follow the measurement instructions. Could there be any other reasons?
Yellow spots on leaves
I have recently had yellow spotting on outer edges of leaves but was able to correct with calmag. Didnt look like pics from the OP, they were right on the edges of the leaf margins. Noticed this was an old post, were you able to identify and correct the problem
All posts and pics are completely fictitious. I found all pics on the internet and lied about my stories on here because I have no friends and want to sound cool.
Yellow spots on leaves
I just noticed this spot on one of my ladies and it's kind of scaring me because I have never seen spotting on any of my babies before, can anyone tell me what it is and is there away to fix it before it get worst