They look like wood-demons, their hair thick and shaggy like a horse's mane. Some of them are clean-shaven, but others - especially those of high rank, shave their cheeks but leave a moustache that covers the whole mouth...". Limewater is used in the preparation of maize for corn tortillas and other culinary purposes using a process known as nixtamalization. This unlocks proteins in the cornmeal, making it more nutritious for the consumer. Eating maize-based foods without nixtamalization or supplementation with legumes or meat leads to a nutritional deficiency known as pellagra. Limewater is widely used by marine aquarists as a primary supplement of calcium and alkalinity for reef aquariums. Corals of order Scleractinia build their endoskeletons from aragonite (a polymorph of calcium carbonate). When used for this purpose, limewater is usually referred to as "Kalkwasser". It is also used in tanning and making parchment. The lime is used as a dehairing agent based on its alkaline properties.