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What is the Keep Box?
The Keep Box is where caught fishes can be temporarily kept to be taken home for feeding and growing in the Tank Room. When a fish is caught, fishermen will get two options, which is to release the fish back to it's habitat or to keep it in the Keep Box so it can be taken home for feeding and growing. The Keep Box has a maximum capacity of 4 fishes that can be kept on a fishing spot. After fishing, fishing again would not be available before the Keep Box is empty, which means that one cannot go to another fishing spot if he/she still has a fish in his/her Keep Box. This can be solved by putting the fishes caught into the tank or release it back into it's habitat.

Lesser Capabilities
Fishes caught from Trolling and GT Fishing cannot be kept inside the Keep Box. Why? Because fishes from these fishing spots need a very large space for them to swim freely like they always did before they were caught. Hence, leaving the fishermen no choice but to release them back into the water.