Help required

[supacel]

Hi Guys and Girls

I'm new to this so please bear with me. I'm having a problem with leaves turning yellow/gold and curling up( see photos attached).
My set-up is in a cupboard(0.5m2)
Its R-DWC with a total water volume of 60.1L
2 15cm flat air stones @ 88L/min air pump
water recirc pump @ 1000L/Hour
1 150 watt platinum LED grow light
Nutes are at about half the manufactures recommended EC of 1.2-1.4
PH stays constant at about 6
Strain is Barneys farm Critical kush @ 23 days old
Have an Algae issue, so flushed the tanks and added 11ml H2O2 35%

Any help of advise will be greatly appreciated!

 

[BuddroGreen]

Algae is from light leaking issue.

LED will cause the plant to use more cal-mag, and usually starts on the bottom older leaves, supplement Cal-Mag.

An EC of 1.2 - 1.4 (600ppm -700ppm) is high for a plant that size, I hardly go over an EC 1.6 (800ppm) in flower, and by that time it's a big plant. I would back off on the EC to about EC .8 - 1.0 @ 5.8pH

 

[Roundman]

Your PH might be a bit high for NON soil growing too.. 55 to 5.8 is usually recommended. but yes, looks like you have a few issues.

 

[supacel]

Hi

Thanks for the replies and advise!

So this is what I have done:
Blacked out both tanks, water and air line.
Cleaned both tanks with bleach
Refilled both tanks with clean Ph'ed water.
EC is sitting at about 0.51 and PH is 5.8

Now I have to wait and see what happens I guess.
I will post pic in a week or so!

Thanks

 

[Dan Ultra]

Those "rusty" spots look like Calcium deficiency. Like Buddro said, Cal-Mag should be supplemented with LED grows. Calcium is a mobile nutrient, so you would see the deficiency in older leaves first then progressing up the plant. Here are some charts to consider

 

[supacel]

Whats up my gents

Just would like to to thank all of you for your input into my little project.
I believe my girls are looking better then ever and i just topped them last night.
Wow and that new root growth within 24 Hours of adding Cal-Mag.(22g for 60l of water.)
So Happy !!!

next on my list is building my screen, I'm thinking of giving it a V-Shape to increase surface area
and my spacing I was thinking of a 3'' by 3''
Once again would love to know what you guys think

Peace ,Love ,Respect
Supa-Cel