Try Drennan double strength for hooklinks - it floats and is reasonably low diameter. Pop a bit of vaseline on your fingers and rub them upand down your mainlinwe and hooklength to help it float (may need to reapply in the session too).
Finally, bubble floats are not the best float for surface fishing. Can be awkward to rig up and are prone to tangles. Try a surface controller float of the Fox bolt bubble floats (v. similar to bubble floats).