I tried out a "prosumer" Canon S3 IS, which was 6.1 pixels, but was considered a nice product in between an advanced point & shoot and a digital SLR. I thought it was a good camera for the money (same price as this one) and it had many of the same features as this one, and took some good shots (better than my old Fuji, which doesn't have great zoom) of my fish:
This one was taken on the highest ISO setting the camera had, which is why it's a bit grainy.
Image stabilization is a great thing to have if you don't have an SLR and want to get shots of the fish. I would bet that this camera can capture really great aquarium shots. Look it up on Amazon and see if there are any consumer-uploaded photos. That will give you an idea of what kind of photos it takes from other people who've tried it out.
1 yoyo loach, 2 polkadot loaches, 6 cherry barbs, 2 turquoise rainbows, 1 chinese algae eater, 2 harlequin rasboras; java fern, java moss, hornwort, Asian ambulia