1. Drano/other drain cleaners
-Drano products are not meant to be used for garbage disposals because they are too strong. Drain cleaning products contain chemicals specifically made for clearing blockages of inorganic materials – things like hair and sludge build-up – in bathtub drains. It is a foaming solution designed to dissolve inorganic buildup while simultaneously not causing damage to the heavy drains and pipes that make up your bathtub. As a result of this, the chemicals in Drano products are extremely corrosive in nature, and can eat away at the plastic lining of your garbage disposal, ultimately destroying it.
2. Cooking Oil
-Leftover cooking oil from frying pans – such as coconut oil, canola oil and olive oil – cool down after being taken off the stove top. When cooking greasy, fatty foods in these substances, the oil can harden and solidify after cooling down completely, often turning to a yellowish color. (If you fry bacon or any other pork product on a frying pan, it eventually turns to lard). This is especially true with coconut oil, which is solid at room temperature and liquefies in hot temperatures. Oils may be liquid when you pour them down your drain, but as they cool down, they can solidify, and eventually create blockages and clog your garbage disposal.
3. Inorganic materials
-Garbage disposals are also known as food disposals, so it should go without reason to say that anything other than solid food should not be placed into it. This includes eating utensils like forks and spoons – metal and plastic alike. The same also applies for straws, napkins and other eating utensils and accessories. Garbage disposals are not built to handle heavy, hard objects like metals and most plastics. In many cases, they will end up destroying your garbage disposal entirely. But keep in mind to much food scarp will also clog the sink drain line bends and eventually develop a impossible clog to rid of unless you hire a professional.
Garbage disposals are meant for disposing chunks of food leftover from plates and other dishware. Putting anything else in them will likely end up destroying the disposal, and will cost you more money in the long run to replace it.