how often are you watering? they look like they are overwatered possibly. it doesnt matter if they have pistis they are clones you can veg clones with pistils lol. are they rooted clones? do you have a fan lightly blowing between light and canopy? also how far is it away from light? if you can hold your hand at top of leaves for a minute without the heat being uncomfortable its agood distance. or even hold your hand like a foot from the light and gradually get closer until it is uncomfortable to get an idea of the distance so that you dont have to keep moving the light

edit: oh and the yellowing is normal for clones as long as the newer growth is green don't worry about nutes just yet wait at least a week