If the canister flush valve or flapper in a toilet does not lift high enough, it will drop down too soon and provide an inadequate amount of water causing a poor toilet flush.
To correct this issue, adjust the chain that is attached to the flapper or canister flush valve. The chain should be taught, allowing for only one to two lengths of slack in the chain. This ensures the flapper or canister valve seal properly and provides the correct amount of chain length for a proper flush.
