Every day, keep back a bit of the fishy ingredient and freeze it, ready for Saturday's pie.
Monday: roast chunks of butternut squash, with green peppers and onions, rubbed in olive oil and cajun spices. Cook for 30 mins, add salmon steaks on top - salmon previously marinated in grain mustard and honey, bake for another 10-15 mins or until the salmon's cooked.
Tuesday: Delia's (tinned) salmon fishcakes, parsley sauce, peas or broccoli. Make twice as much mash as you need and freeze it for use on Saturday
Wednesday: Prawn and mushroom risotto with white wine and loads of Parmesan (veggie version if that matters to you)
Thursday: Monkfish curry using monkfish if you can afford it, ling if you can get it, or cod if neither of those apply!
Friday: Delia's shallow-fried fish, chips, mushy peas
Saturday: Cheesey fish pie using frozen mash from Tuesday and any leftover bits of fish from the week's meals, plus hardboiled eggs, parsley, capers etc. etc.
Sunday: Scallops pan-fried in butter with creamy mashed celeriac and oven-baked crispy kale (cooked like 'chinese seaweed', ie rubbed with oil before baking, sprinkled with salt and pepper and maybe crushed cashews).
Hope that helps a bit!