The clock starts when the fish leaves the water, not when you get home. In Kuwait every warm minute costs quality you cannot get back.
For larger fish, bleed and gut them as quickly as you can. Blood and gut bacteria are what turn good flesh first, and this does not need a fancy kit — a sharp knife and clean water are enough.
Some anglers prefer to keep fish alive in a keep-net or an aerated tank until the session ends, which works well when the spot allows it and there is shade. Where the water is warm, still and not refreshed, a tank stops being a solution and becomes the problem.
The best option is a slush of crushed ice with a little seawater, where the whole fish is buried and contact covers the entire body, cooling it far faster than a layer of ice piled on top. Crushed ice in a good insulated box is next best, but remember the ice has to surround the fish, not just sit over it.
Do not simply drop fish into a bucket of sea water and call it chilled. Sea water is far warmer than ice, and the fish's temperature stays high while you believe it is fine.
As general food-safety practice, fish kept properly on ice holds good quality noticeably longer than fish kept warm. Above roughly 4°C the decline is fast — smell, texture and colour all change. The practical rule: if the box is not brought down to temperature quickly, your catch drops from fresh to average within hours. Enough ice before you load the boat matters more than most of the tackle you carry.
For longer storage, portion the fish into meal-sized pieces, wrap each one tightly, press the air out of the bag, and label it with the date — in a month you will not remember what it is. Use it within a reasonable period in the freezer; the shorter the time, the better the quality. Refreezing already-thawed fish drops quality again, so freeze once, in the sizes you will actually use. Thaw in the fridge overnight, never on the counter and never in hot water.
Hygiene is not negotiable. Wash your hands and knife between fish, and never use the same board for raw fish and ready-to-eat food. Raw fish on a surface that later holds bread or salad transfers problems you do not want.
B7R's catch log makes all of this easier: you record what you caught and when, then look back and see which trips actually produced.
Storing your catch is not the chore after fishing, it is half of fishing: ice early, water drained, clean hands from the first minute. Download B7R free on Google Play: https://play.google.com/store/apps/details?id=com.q8dm.b7r — sea state, Shuwaikh and Shuaiba tides, fish guide, catch log, seasons, navigation tools and an SOS button.