I bought my tank just for my cat: he's the "Xaltd 1", I'm simply his humble servant posting on his behalf. He adores watching them, and never gets his paws in the water (but I do have a full hood!)
I WISH he'd be an indoor cat!!! He just HAS to be outdoors (unless it's snowing, raining, too hot, too windy). I have him microchipped & I have insurance (yup, they sell cat insurance!). He's a wicked hunter, and brings me "dinner". It's live by the sword, die by the sword with him. He IS huge and really tough, but I can't believe he's lasted 8 years w/o incident. We have fishers & coyotes.
4 bettas: Butch, 3-year-old violet male PK EE & 3 girls in a 30 gal sorority. I do not name the girls anymore! 1/2 of them die within a month.
30 gal: 9 Oto cats, 4 Ocellifer cats. Inverts: Cherry shrimp & 2 assasin snails.
10 gal.: Butch, his 5 oto cats, 3 assasin snails, and a few snails the assassins haven't caught.