Hi there. Complete DIY numbskull here. I have these lever style taps in my kitchen. The two issues are that one is dripping very slightly, and one can't be tightened up a great deal. Underneath there seems to be a circular/smooth nut of some kind that just fastens it in place but it's too hard to grip and tighten a great deal. Never fitted taps etc - is there some kind of sealant placed under the rim of the tap which will secure it in place? Guess that's what the residue is round the bottom?
Thanks in advance.