This kind of casual game is aways interesting to play. Is it free to play or users need some amount of ETH to play regularly?
Also, is it possible for people to earn some reward in Ethereum while they are playing the game?
It is better to have food for your fish, but if you have the biggest fish, you can not feed it, because no one will bite it. You can also feed your fish by hunting. All the air enters the fish and it can only be removed by destroying the fish.