Growing troubles

[Robb]

Morning folk!
 
Second year growing peppers, One of my santé fe grandes has started having some strange leaves. The 3rd and 4th set of true leaves have started to curl down, there is no yellowing or crispy bits and as far as I can tell they look healthy.

Anybody got any ideas what could be causing this? The grow area is at a constant 20-30 degrees all indoors.
 
There is some new growth on the plant, 5th set of leaves which don't appear to be doing the same (yet) so possible it may just be strange growth?
 
http://imageshack.com/a/img854/5118/pd9h.jpg
http://imageshack.com/a/img837/2343/p1f2.jpg
http://imageshack.com/a/img842/1095/fcjr.jpg
http://imageshack.com/a/img829/4218/ex1h.jpg

 

 

[Mallory]

It looks like you may be under watering. Sante fe grandes like water and that soil looks very dry. If it is constantly 85F the soil could be drying out really quickly even if you are watering regularly, and that causes the type of leaf curl pictured. The plant looks like it is generally healthy, but under environmental stress of some kind. If you have been keeping the soil too wet, leaf curl can also happen from over watering. 
 
K deficiencies can cause leaf curl, as can over-fertilizing, and you could also check the underside of the leaves for any pests, and check the leaves for discoloration or spots which may indicate virus or bacteria, but the leaves look very green to me in the photos.