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Basically just head over to the Gaia Aquariums forum. Look at the Forum Pulse and just click the first thread you see, and scroll down to the tank. It's pretty much impossible to miss. The tank will be covered with the words "Booty Grab" and there will be a button to play. Just click and it'll be a link to the tank.
Once there, you may have to type in two words for security purposes. After that, you'll see a screen with all the fish that are glowing for the moment. It'll start a 5 second countdown, and then the game begins.
The object of the game is to catch as many coins as you can using the shell your avatar has on his/her head. Move around by sliding the mouse back and forth across the aquarium.
There will be bubbles coming out of the sides of the screen that are either good or bad. Make sure to avoid the bad ones (usually red colored) and try to get as many of the good ones (usually blue colored) as you can. They can give you things such as enlarging your shell, speeding you up, and more.
I hope this could help you understand better!
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