Seafood is plentiful over summer yet shoppers tend to be conservative and stick to the big name swimmers with the big cost per kilo, rather than sampling some of the country's 100 other edible fish.

There are plenty of alternatives to the pricey snapper and tarakihi.

Nigel Thomas from Auckland Fish Market says albacore tuna, known as the chicken of the sea, is a great alternative. He says gem fish, creme fish and porae are also excellent.

With shellfish, says Thomas, surf clams and diamond shell cockle are bigger and therefore have more meat.

No matter what fish you buy, it's got to be fresh, which means very little smell, other than that of the sea. Whole fish should have clear eyes, with a black (not cloudy) pupil and a translucent cornea.

The skin should be bright and firm, with a glossy sheen, and gills should be a bright pastel rose. Fillets should be translucent and firm, with an elastic texture. Avoid fillets that look yellowish, dry, or slimy.

Avoid shellfish with cracked or damaged shells; they are likely to have died. The same goes for shellfish that don't open when they're cooked.

The key to safe storage is temperature. Storing your catch on ice until refrigerated is imperative. In the fridge store whole fish, fillets or other types of seafood on a large plate or dish, and loosely cover with plastic wrap to prevent it drying out.

Ideally, cook it the day it is bought or caught.

Depending on how fresh it was when first refrigerated, correctly stored fish can be kept for four to six days provided it is kept at a safe temperature. Shellfish and crustaceans (such as prawns and crayfish) are best eaten on the day of purchase.

Fish or shellfish lose one day of shelf life per hour stored at room temperature. So in the sun or beside the oven, deterioration is much quicker.

Thomas says the best way to cook fish is by keeping it simple. Don't drown it in rich sauces and don't overcook it. There's nothing quite like the taste of fresh fish melting in your mouth.