hi yer there r two things u can do one is change dounut rubber ring for ideal stanard one which is much fater ifthe one u have is a thin bit of rubber any good plumb centre will sell them 2or 3poundsor if the one u got is as big then u need to make sure the syphon nut is tight and not leaking from there which it might b the rubber sits snug around nut whenu put cistiem on the bowl and u can add some clear silcone to top and bottom of rubber to seal it if u want also do not over tighten nuts as it will leak down the theads as well and keep cistiem as straight as poss and level
steve
April 2012