My cat loves my dojo loach. It is the only fish she really pays any attention. He begs for food from her and swims all over the front of the aquarium when she is sitting there.
My cats like the loaches best--they stay at the bottom, and the cats can race around and follow the fish. They ignore all the SW fish, and the tanks that lack loaches.
One of my cats spends a few hours a day watching my dwarf puffers, i have 9 of them in a 29 gallon, and he is always batting at them and bashing his head into the glass trying to get inside it lol. He leaves my other tanks alone, never shows interest in them.
i odn't think one of my cats noticed the tank so much except i would sit on the floor...he would crawl in my lap. now, he sits tthere and watches the tank. anything active...and cories especially. their activity level for one, and i think that since they make such quick movements when they surface it stimulates the prey drive in cats. definitely keep it covered. #1 anyone see that funniest home video years ago when the cat fell in the fish tank? #2 gone fishing. you couldn't turn your back on a previous cat of mine . i so much as walked away with a bucket of water to dump adn i can hear his paws going 100mph in that water....he had also caught african clawed frogs out of a tank! :dive: