Uhm, I don't suggest that. Aquariums are bad for rats, poor ventilation.
Try getting two seperate cages and, after proper quarrantine, begin the introduction process.
You can start out by placing the cages side-by-side or near each other so they may get used to the other's scent and sniff each other out through the bars.
After a few days like that you can place them in neutral territory(somehwre neither rat has been, most commonly used it the bathtub) and let them meet, groom, play, wrestle. At this time an essential saying comes in need: No blood, no foul. They may argue about who's the boss, but as long as no blood is drawn do not stop them. Anf if problems do arise, do not use your bare hands to separate them! You can wear thick gloves or spray them lightly with water. If, after a few mettings, they seem to get along, you can switch their cages(place Rat1 in Rat2's cage and Rat2 in Rat1's cage). While doing this, it's good to prepare the cage they will both be put in by cleaning it out thoroughly with a blach/water solution.
When you feel they are ready, you can put them in their new home at the same time and keep an eye out on them.
Honestly, this is just one way to do it. Others may have more suggestions.
Aquariums aren't always bad. There are pros and cons to every cage type out there. The ventilation isn't always great, but cleaning the cage daily helps in my experience anyway... The way I introduced my two girls was just put them together on the couch...i didn't worry about the quarantine period because they came from the same place and were housed together before anyway... But when I get my rescues I will definately do a proper quarantine. your method could work... but I think it would be less stressful to put them directly together so as they can properly smell each other right off the bat.
Thats not what I'm implying in the least, letting each rat free roam a neutral territory is the best way to socialize the two, that way they can sniff each other out without having to be territorial its the way i do intros for ALL of my animals, and since they're introduced under supervisation, I have never seen blood shed.