You nailed it. I honestly don't think the "peat moss" makes for a good medium, and could see where it could be throwing the PH thus causing the leaves to twist, and also the yellowing. If it was me, I would place them into another medium. Such as a good organic soil. Add alittle perlite, and or vermiculite, and I bet my left nut it'll fix the issues..
As for the Fish Emulsion. I use that "only" when I have any issues with any of my ladies. The reason I do that is because its a good NPK ration of all the nutes they need during "veg". And veg only. Your going to need something with a higher Phosphorus and also Potassium for flowering. Other then that they are looking ok, but my honest opinon they could be looking SO much better if you would do that.