Aquariums are good for small children because they are hard to knock over. They are also easy to clean and give a clear view of the  hamsters. However, heat can build up and cause heatstroke, especially if it is near a window. Another con is that aquariums do not get much air. The top of an aquarium must have holes or a mesh so that the hamster can get some air. These cages are also very neat because bedding cannot spill out. Furthermore, my Syrian hamster had occasionally tried to eat the silicone in the corners of his aquarium. I have not read that this could happen anywhere, but it may be a problem. Aquariums are also good because you can easily pick up your hamster without him escaping because of the high walls. Aquariums can be hard for children to clean because they might be too heavy to pick up and dump out the bedding. Alternatively, you can use a scoop to get the bedding out, though it is very hard to get all of it out.