Tank 5 is the final tank in Insaniquarium Deluxe. Unlike all other tanks in the game, this tank is composed of only one level, a boss battle with Cyrax. This tank takes a twist on the main gameplay, where the mission now is to defeat Cyrax as soon as possible while protecting your Pets. The Aliens are constantly at attack in this level and the egg piece does not cost any money. There are also no food upgrades, laser upgrades, fish and there is no food chain.
- Stinky the Snail
- Niko the Oyster
- Itchy the Swordfish
- Prego the Momma Fish
- Zorf the Seahorse
- Clyde the Jellyfish
- Vert the Skeleton
- Rufus the Fiddler Crab
- Meryl the Mermaid
- Wadsworth the Whale
- Seymour the Turtle
- Shrapnel the Robot Fish
- Gumbo the Angler Fish
- Blip the Porpoise
- Rhubarb the Hermit Crab
- Nimbus the Manta Ray
- Amp the Electric Eel
- Gash the Shark
After beating the final level and defeating Cyrax, the player earns 5000 shells and a special credits scene is unlocked. In there Angie will revive any pets that have died. Then, it will show the cast of Insaniquarium (all the fish, pets, and aliens), and then the staff behind Insaniquarium.
There are 6 possible messages you can get, depending on how many pets have survived:
- 1-7: No message
- 8-12: Also, you saved a fair number of pets yourself. Good job!
- 13-14: Hmmm... actually it looks like not that many pets died. Great work!!
- 15: Whoa, hold on... Only 3 pets died?! That's incredible! Good shooting, there!
- 16: Whoa, hold on... Only 2 pets died?! That's incredible! Good shooting, there!
- 17: My goodness! That's it? You only lost one pet?! That's unbelievable!! How the heck did that happen? You rule this game!!
- 18: Wait a minute! You didn't lose any pets?! How did you do that? That's really amazing! Seriously though... How did you do that?? Fine, keep it to yourself!
After this message, it will say "Thanks for playing. We'll see you next game".
- When the Aliens kill all of the player's pets, the Game Over dialog box will read "Oops! All of your pets have died!", which is the regular Game Over dialog box but with the word "pet" replacing the word "fish".
- The death sound of a guppy will play if any of the pets were hit by Destructor's missiles or Ulysses' energy balls. They will simply despawn when this happens because there are no sprites of each pet's corpse.
- Tank 5 has no real theme, due to the entirety of the Tank taking place during an alien attack.