there is a blockage either in supply pipe or refill valve.
litres
On the inner rim of your toilet where the water flushes out from the cistern, if these small holes are blocked it wont make the right angled pressure to flush a toilet
Iron in the water would cause rusty stains in the toilet.
diabetes
Why would you want to know that?HUH?!
Improper venting.
A wooden rain cistern is constructed very similarly to that of a whiskey barrel. However, those of us that have the equipment and knowledge to build a rain cistern (if we wanted to) know that the cost of the materials for a wooden cistern let alone the time to build it would cost considerably more to construct than purchasing a plastic or concrete water cistern. So if you are asking your question for the purposes of cost of a cistern, plastic and/or concrete are the way to go.
i dont no but that is nasty why would you do that
My toilet is doing the same thing this morning. We had a big rain last night. Could this be part of the cause?
You probably need to replace the wax ring and possibly tighten the two bolts that hold the toilet to the floor.
That would be your flush valve in the tank
You would replace a flush valve or 'flapper' when it gets distorted or leaks slowly as they all eventually do. Take it out and go to Home Depot and you will see many better ones than there were when your toilet was made. Average cost $6-10.