Waterproof sealing tape

EvoStick do a leak repair putty that sets even under water. No idea whether B&Q or Wickes sell it though. IME, Wickes almost never has the thing I want, but that may just be me wanting odd things.

Maybe self amalgamating tape? BUT, the technique about applying it will not be that obvious for someone who hasn't used it before or seen it being applied.

Always worth practising winding it around a pencil/pen first, leaving it for 30 minutes and then trying to remove it.

Colin, thanks for that. It seems I had the wrong end of the stick: apparently, the outside of the connector can be dried off, so a conventional tape might be OK for a temporary fix. I've just posted a corrected message asking if there's a partiuclar brand or type that might be best.

Alan_m, thanks. You might have seen my follow-up: apparently the surface can be dried off, so a conventional tape could be OK for a temporary fix.

Denso tape or what was syglass tape will stick to anything - its a kind of putty impregnated fabric that is wrapped round and then massaged into place. Often used for corrosion protection of pipes.

Thanks, John: I'd not heard of that.

That's very good for repairing electrical cables, but does not stick well to all surfaces, so you can still end up with a leak path if used over a leaking pipe.

It will not "stick" to a greasy surface. It does not actually stick to anything except itself. The act of stretching the tape as it is being wound a pipe gives a result much the same as using a rubber band to seal something.

It is/was sold on a popular shopping channel as a leak repair tape along with a demonstration of someone repairing a copper pipe with water gushing out of it.

As usual with things being demonstrated on these type of programs or at trade shows it is not a real world situation. Water pipes are often fitted a cm away from the wall and getting easy access to the back of the pipe to wrap tape around while stretching it to twice its length is a bit difficult. In the studio demonstration the pipe is in a glass tank with clearance all around the pipe. The person demonstrating could easily stretch the tape and wind it around multiple time in a few seconds. It was also sold at 20x the price of the equivalent from Screwfix/Toolsatan/Ebay.

Is she sure its the joint and not the tap? I found that my tap was seeping through where the spindle went into it but it was kindof trickling down the pipe and dripping off not at the first joint but the Second where there was an elbow. Brian

Brian, thanks for that, but perhaps I'm misunderstanding you: there's no tap involved. The problem is at the lower end of the pipe which connects the cistern to the loo.