Hi,
I have a dual flush cistern in my bathroom toilet but it does not always flush satisfactorily. The level of the water after filling only comes about 1/3 of the way up the cistern. If I fill the cistern up a further 1/3 by hand the flush is that much better. However, I understand that if I can adjust the ball valve the cistern may then do this automatically when flushed. My problem is that I do not know how to adjust the ball valve! I have a photo of the interior but I do not know how to upload it as there appears to be no upload button on the page. Any help please?