Time Trial mode is another mode which tests your money-making skills over a limited amount of time. Each tank is unlocked after completing a tank in Adventure Mode (e.g. After completing Tank 1 in Adventure Mode, Tank 1 is also unlocked in Time Trial Mode).
In Time Trial Mode, there is no egg piece to buy. Instead you have to purchase a random egg which contains a random pet. You can keep purchasing random eggs until all your pets are in use. The random egg prices follow a pattern that the initial price will be doubled and that will be the price of the next random egg.
The goal of this mode is to earn as much money before time runs out. In Tank 1, you have 5 minutes. In Tank 2-4, you have 10 minutes. From the money you earned, 5% will be taken and converted to shells, and added to your balance.
Money-making pets are recommended in time trial, since the goal is to earn as much money as you can before time runs out. A good pet combination is Amp, Angie, Presto, and Walter. Clicking on Amp turns guppies into diamonds while Angie revives them. Click on Walter to activate Amp or make fish drop coins. Turn Presto into a copy of Walter, and during alien attacks, Gash or Gumbo. The recommended pet limit for tank 1 is 4 pets and for tanks 2-4 6 pets.
Pets: Amp, Angie, Presto, Walter
Turn Presto into Shrapnel for money. After 1 minute, change Presto into Blip to unlock the options. When the first alien comes, change Presto into Gumbo or Gash, then to Walter or Blip afterwards. After that, click on Amp to shock the guppies for diamonds, then buy a carnivore. Buy up to 5 carnivores before buying an ultravore. Keep using Walter to activate Amp and make the ultravores drop treasure chests for money. You may buy some random pets to help you.