You have some severe stunting and deformities which could be either due to bugs, or more commonly pH like you suggested. The bugs could either be white flies/spider mites or aphids that suck up moisture from your plants, cause leaves to shrivel and grow stunted. Make sure your spraying your plants with some form of organicide and heighten your pH a little if it is too high. I find 5.5-5.8 to be the best range for hydro.