Hrmmph... I never noticed that full color was an option... I was still using 1-bit BMPs!
MA2.6 let you put PNG files into C:\Program Files\SereneScreen\Marine Aquarium 2.6\ and it would rotate between them. Full color and transparency and everything.
But the "Import Logo" button inside the Aquarium only loaded BMP files.
It always took 3-4 times trying to explain to people that YES you can do PNG but NO you cannot load PNG inside the Aquarium, you have to place the folders in the right folder.