hi mate, if it was nute burn you would see the edges of the leaves burned and yellow, but you only have a small amount of this at the ends so i dont think its a nutrient problem as such, also the leaves are cupping up so temps are still high, cant remember if it was your plant that had the cupping before ill have to check, but if the leaves are cupping up at the ends then this is a clear sign temps are slightly high, they cup up so they can catch more wind which releases more moisture and cools them down, indoors they dont have this luxury so we either use fans and keep them coil or raise the light a few inches until the problem is resolved.
is it just the lower leaves that are affected, if so are these leaves getting any light, leaves turn light green then yellow if their not getting much light, also with young plants if the light is to close it can cause the leaves to bleach but this would be more noticable at the top of the plant.
also let us know what nutes your feeding and how often,
i just read your comment above, you have not fed any nutes at all, is this what your saying, if so how big is the plant and how long have they been in the pots their in,
also how often are you watering, are you letting the pot pretty much dry out before watering again,
let us know as much as you can then we can see what can be done to sort it out, it could be that it might actually need some nutrients, the yellow at the ends of the leaves looks like its been their a while so chances are the soil was to hot at first but now they might need a weak nutrient feed but depends on age of plant and how long they have been in that soil