Wierd Rust color

[Mr.greengenes]

I am growing a AH3 and it is experiencing some unknown defeciency any help would be very helpful! Thanks

How long has this problem been going on? slowly about 2 weeks
What STRAIN are you growing?Arjan Haze 3
What was the establishing technique? from seed
What is the age of your plants? 5 weeks
How long have they been in the soil mixture they are in now? 4 week
How Tall are the plants?7 inches
What PHASE are the plants in? veg state
What Technique are you using? (SOG, SCROG etc) 4x4 closet
What size pots are you using? 1 per 6'' plastic bag
What substrate/medium are you using? FFOF with 25% perlite
What Nutrient's are you using? Advanced Nutes Sensi Grow A+B
How much of each nutrient are you using with how much water?4ml for 1 gallon
How often are you feeding? every other watering
What is the TDS/EC/PPM of your nutrients used?800ppm
What is the pH of the "RUN-OFF"?750-850ppm
What method of pH test was administered? ph/ec combo pen
How often are you watering? every 2-3 days
When was your last feeding and how often are you feeding? 2 days ago
What size bulb are you using? 400 watt MH
What is the distance to the canopy? 15"
What is your RH Factor? 20%
What is the canopy temperature? 75 degrees F
What is the Day/Night Temp? 60-65 degrees F
Tell us about your ventilation, intake exhaust and when its running and not running ? always on with lights
Is the fan blowing directly at plants? no, it is blowing off wall
Is the grow substrate constantly wet or moist?no i let it dry b4 i water
Is your water HARD or SOFT? the ph is 7.54
What water are you using? RO h2O
Are you using water from a water softener? no
Has plant been recently pruned, cloned or pinched? no
Have any pest chemicals been used? If so what and when? no
Are plant's infected with pest's? none

Thanks Again All!

 

[pokerfish]

Can't see the pic- very, very dark. Rust speckling usually Mg though. Did you prep with lime and/or apply a cm+?

 

[irieeyes808]

man maybe over on the ferts?

 

[Purple_trees]

Mg def

 

[MJane'spoontang]

Weird, I'd say that rust is usually associated with Cal and not Mg (though those deficiencies do go together) but this doesn't looks like cal to me. What is the pH of the runoff, in the questionnaire you give the ppm instead.

In stitch's guide it looks kind of like a boron def. but then it says that boron effects only the new growth. Do you have a pic of the entire plant?

Fuck, I really wanna figure this out with ya. I hate these mystery problems.