To fix a slow toilet and retain flushing power, remove any full or partial clogs and then remove any hard water deposits with a muriatic acid wash. Some toilets may have been manufactured with defects that cause slow flushing.
Toilets that flush slowly could be doing so because of a partial clog or hard water deposits.
- Test for a clog Fill a bucket with water. Pour the contents into the toilet quickly, without splashing water out of the bowl. Flush the toilet. If it flushes well, there may be another problem. If there is still a slow flush, then there is likely a clog.
- Remove the clog If there is indeed a clog, plunge with a plunger to remove the clog and test the toilet by flushing again.
- Check the manufacture date If there is no clog and the toilet still flushes slowly, then another problem is present. Older toilets may have manufacturing problems. Toilets made between 1994 and 1997 are first generation low-flow toilets and have issues that cause them to flush poorly that cannot be corrected.
- Remove hard water deposits Hard water deposits build up in the bowl rim holes and the siphon jet hole. These can be cleaned manually, but a simpler method involves a diluted muriatic acid wash. Ventilate the area. Mix the acid in a 1 to 10 ratio with water and pour 1/2 of the mixture into the overflow tube in the toilet tank. Leave the acid wash to work for 30 minutes and then add the remainder to the overflow tube. Wait another 30 minutes and flush the toilet.