Toilets, Sinks, Showers, Tubs and Disposals - Toilet tank gaskets

My toilet started leaking and I thought it was the cheep plastic hose that goes from the wall to the tank. Well it wasn't! It turned out to be the gasket between the tank and the fill tube. Well after looking closer at the different rubber parts, all the rubber in the tank is corroded.

What could cause this? Should you change the gaskets every so many years? I noticed the new parts have a 5 year warranty. Does that mean after 5 years you should replace the rubber parts again? The gaskets were black rubber and it was completely broken down. The water dripping off the rubber was black and when I touched it I had black rubber on my fingers.

Chemicals in treated water supplies will cause rubber to deteriorate.also if you use bleach based cleaning products that are placed in the tank this speeds that process up considerably.It is a fact of life with toilets that the rubber parts go bad.5 years would be good for a flapper most don't last much more than that.The other parts vary.

Thanks for the reply. The problem was it happened in a guest bathroom and no one goes in there very often so I found an inch of water on the floor and it soaked the carpet and ruined wood flooring outside of the bathroom.

Add that to the list of things to keep an eye on!