Cool idea but I would definitely think about how much weight your putting on a dresser that doesn't seem to be reinforced. A 10lb tank is about 85lbs when filled. The 20 you have on top is already bending your dresser in the center from what I can see in the pic, a 20 filled weighs 160-170lbs.
I'm not trying to be a downer, just keep it in mind. I would put some extra support for the tank you already have never mind the new one. And if you plan on opening the fish tank like a drawer? your asking for disaster.