Plant turning light green.... help!

[Wellonsk]

NEW TO THIS:
My ghost pepper, Trinidad scorpion, and chocolate habanero are all turning light green and not producing much fruit. While my white habanero and Carolina reaper plant are doing very well, dark green leaves and huge and producing lots of fruit. I have been doing the same thing to every plant so i'm not sure why some of them are struggling. What could be causing this and what can I do? (Sorry about the crappy pic quality and that some are sideways, i'm crunched for time and off to work!)
 

<GHOST

<Chocolate

<Scorpion
 

<Reaper

<White Hab

 

[Chorizo857_62J]

You could try some epsom salts (Mg), in a solution with a spray to the leaves, or to the pots directly.  don't over-water though.  Things don't look too dire.

 

[Chile Jim]

I've seen similar symptoms in some of my pepper plants, especially the choc hab pic. In my case it was either a lack of calcium or a mite infestation. With the mites, the leaves started to curl and look a little crinkled and new leaves became deformed. Plus, there was bronzing on the underside of leaves. I sure hope it's not a mite attack. 

 

[CMJ]

What are you feeding them and how often? They just look like they need a little Nitrogen to me. Wouldnt hurt to give them larger pots and some fresh soil.

 

[Gorizza]

I would say nitrogen over magnesium, magnesium deficiency is a stranger pattern in the leaf and nitrogen is more uniform (though it varies in the plant top to bottom). fertilizing with both wouldnt hurt though.
 
can we get a close up of a leaf upper and downer?
 

 

[Mr. West]

I don't think it's as simple as nitrogen deficiency.
The scorpion has greener bottom leaves. 
I think they've been slightly overwatered for a time. If so, it's a minor problem now, but you should correct it.
Look at the chocolate picture. The leaf in the front and center has puffed up between the veins.
The plant does this to try and increase transpiration to move some of that excess water. 
Also, a period of overwatering may have inhibited calcium uptake (same picture, leaves in the back-right side is cupping).
Extended wet conditions can also appear as Nitrogen deficiency, but you probably don't need to add Nitrogen right away.
Just water less frequently those that are struggling. After that, you can feed a mild nutrient solution if you like.
 
You say you're treating all the plants the same.
Well now that you recognize they're not as vigorous, don't continue to water them as much as the other two that are thriving. (Feed these regularly, as you are. They have more and healthier foliage, so they will be drinking faster.)
Treat each plant according to its individual needs. When one needs a refill, another plant might still be working on its last pour.
 
Also, not sure how hot it is there... but if you are overwatering because you see them wilting in the midday sun and you think they're thirsty and ready for more water (common mistake), then you may want to instead relocate them for part of the day to give them some partial shade or filtered light. You can also use a shade cloth or mulch the pots to shield topsoil from the sun and provide evaporative cooling.
 

 

[Wellonsk]

Thank you so much. I think over watering may be my issue. I did find them wilting in the middle of the day and watering them to bring them back. I will try relocating them to a different part of my yard and hopefully things will improve.

I don't think it's as simple as nitrogen deficiency.
The scorpion has greener bottom leaves. 
I think they've been slightly overwatered for a time. If so, it's a minor problem now, but you should correct it.
Look at the chocolate picture. The leaf in the front and center has puffed up between the veins.
The plant does this to try and increase transpiration to move some of that excess water. 
Also, a period of overwatering may have inhibited calcium uptake (same picture, leaves in the back-right side is cupping).
Extended wet conditions can also appear as Nitrogen deficiency, but you probably don't need to add Nitrogen right away.
Just water less frequently those that are struggling. After that, you can feed a mild nutrient solution if you like.
 
You say you're treating all the plants the same.
Well now that you recognize they're not as vigorous, don't continue to water them as much as the other two that are thriving. (Feed these regularly, as you are. They have more and healthier foliage, so they will be drinking faster.)
Treat each plant according to its individual needs. When one needs a refill, another plant might still be working on its last pour.
 
Also, not sure how hot it is there... but if you are overwatering because you see them wilting in the midday sun and you think they're thirsty and ready for more water (common mistake), then you may want to instead relocate them for part of the day to give them some partial shade or filtered light. You can also use a shade cloth or mulch the pots to shield topsoil from the sun and provide evaporative cooling.