Toss salt through zucchini and place in a sieve with a bowl underneath. Leave to drain for an hour. Place yoghurt and lemon zest in a bowl. Pound garlic and salt in a mortar with a pestle until a paste forms. Add this to the yoghurt then stir through. Reserve.
Squeeze excess moisture from zucchini and place in a large bowl (you should have about 750g left). Add grated haloumi, dill, pepper, breadcrumbs and egg. Stir to combine; mixture should be dry enough to handle. Do not leave to sit for an extended time as more liquid may leech from the zucchini, making the mixture more difficult to handle.
Divide mix into amounts a bit bigger than a golf ball and form into patties.
Heat oil in a large non-stick frying pan over medium heat. Shallow fry for 2 minutes on each side or until golden brown and heated through. Serve fritters on a platter with lemon and garlic yoghurt.