Que me pueden estar mostrando las hojas??

Need more info to make a determination. Soil medium, pH value, nutrients used, temps, humidity, light distance. All that stuff helps to dial in a diagnosis. Complete shot of the entire affected plant also helps a lot. Where on the plant the issue is happening is as important as seeing the damage on the leaf itself. Where on the plant it's occurring can greatly help to diagnose. Because if it's on the upper half, or lower half, or all over the plant, all means something and can determine different resolutions.