My nails seem to keep splitting in layers on the tips. what causes that. could i be lacking something?

Most commonly water: Frequent wetting and drying of the fingers is the single most common cause for fingernail splitting. You may also have splitting as a result of a underlying dermatologic condition, or familial. Another common cause of nail injury is fingernail polish and polish removal both of the chemicals can cause nail injury.

Nail Splitting: Nail Splitting is usually cause from exposure to harsh chemicals like detergents, water and nail polish remova. Rarely it is a cause of a vitamin defiency. Iron deficiency could cause brittle nails. A blood test could determine this as well as a good history such a heavy menstrual period, and also after birth where your body has been exposed to acute blood lost during childbirth

Nail Dystrophy: Harsh chemicals, too much water exposure, acrylic nails, psoriasis, hypothyroidism, nail-biting, deficiency in biotin and B vitamins, fungal infections can all cause it. Please see your primary care physician or dermatologist to rule out medical causes and let your nails rest. Jello.Bag balm. http://www.mayoclinic.org/healthy-living/adult-health/expert-answers/split-fingernails/faq-20058182