hydroponic Passive hydroponics leaf problem - what could it be?

[SteffenMB]

Hi 
 
I hope you can help me find out what I am doing wrong.
 
I have about 16 chili plants in passive hydroponics, and about 6 of them show signs on the leaves that something isn't quite right. Especially the chinense's show these signs.
 
The leaves are a bit on the bright side, and they have a lot of 'bright spots', and a few of the bright spots turn brownish, but mostly it just a rather bright green leaf with these brighter spots on them. Here are some pictures:
 

 

 
 
I am using GHE Flora series and following the instructions on their chart. My PH is 5.9-6.2 and PPM is about 650-700. 
 
Do you have an idea what could be off balance, and what I can do to correct it? Thanks for any help.
 
/Steffen

 

[Weed]

looks like not enough magnesium

 

[SteffenMB]

Thanks. Is there an easy fix to that? Like putting a bit more of one of the bottles (grow, micro or bloom) in the mix?

 

[Weed]

well you could buy some cal-mag
 
or you could use epsom salt foliar fed or in your rez 1 tsp / gallon

I dont know where you'd find Mg in those nutes. A quick foliar feed will resolve the deficiency but I think also you're just underfeeding. Seems like some low ppm for a plant that big. I'd do a foliar feed with the epsom and then a regular fert, maybe stronger, in the roots.

 

[ebh]

Bloom has the most magnesium out of the flora series. I use about 900-950ppm on my dwc and it looks healthy, if that helps. With tap water and a ratio of 3-2-1 of bloom-micro-grow.

 

[SteffenMB]

Hmm.. Maybe I should try to go a little higher with my ppm, and if that doesn't help, I'll go look for cal-mag.
Is there something I should be aware of, when adding cal-mag to the GHE Flora series mix? Maybe a lower dose of cal-mag than 'normal' so I don't over do it? I am newbie at this, so a bit afraid I might create a new problem, because of some rookie mistake :-)