Congrats, all the newbies are adorable. I'm sure you'll do great with the rattie and hammie, but the goldfish concern me. Just in case you don't know much 'bout goldies, they get very big, poop alot, live along time, are pigs(food wise), need aerated water for oxygen, clean water constantly, they are coldwater fish, and the kind you have look like common goldies. If you plan on keeping them, I'd suggest getting at least a 10g and upgrading later, a rule of thumb with goldies is 10g of water for each fish. Remember to cycle the aquarium and do not buy a plecostomus(suckerfish) unless you are commited and know of the consequences. I did this, know I'm stuck with a cute lil pooping maching.lol. If you already knew this, then just ignore me. But, if you want more help, feel free to pm me. Best of luck and I intend not to offend or discourage, just inform.