I have a lungfish. His name is Pneumichthys, which is ancient Greek for "breath fish". Of the three kinds of lungfish, he's one of the friendlier species -
a South American lungfish, or
Lepidosiren paradoxa. The African species tend to eat anything that will somewhat fit in their mouths, whereas you can keep a South American lungfish with other fish (within limits, of course). And the Australian species is endangered and very difficult to find in the aquarium trade.
Currently, Pneumy lives in my 40 gallon "breeder" aquarium with about 8
"emerald eye" rasboras , a single female platy* and a lone
yo-yo loach**. The tank is planted with several flavors of
Cryptocoryne, some hornwort, Java moss and Java fern.
During the first 3 or 4 months in Austin, I worked at a local aquarium store - Pneumy had been there from day 1, but he was all the way back in a neglected tank at the end of a row. He was just a tiny worm baby, but I noticed him and built him up a nicer tank and started feeding him live blackworms. Once that started, he finally began to grow, but I think that being neglected at such a critical point during his development has left him stunted. Currently, he's only about 10 inches, but he's at least a year and a half old.
I've been feeding him on frozen "shrimp ice cubes" and shrimp pellets once in a while. I just take a bag of the smallest cocktail shrimp, blend them up in the food processor until they're in bite-size chunks, then portion them out into ice cube trays and top them off with a little bit of water. MUCH cheaper than buying commercial frozen fish food at a pet store. He's picky though, and didn't like the frozen Tilapia cubes as much as the shrimp, nor did he like the expensive beef heart I got from the pet store. Sigh.
The thing about Pneumy is that I think of him like one would think of a dog or a cat - he's going to get rather large (possibly 3-4 feet) and live for a long time. The Shedd Aquarium has an African lungfish, named Grandad, who's been there since 1933.
And in about 30 days I have to move them all to Chicago...
* The last of a 4 generation Platy "dynasty" from my Knox days
** I started out with 5 loaches, and after a heater malfunction and at least two suicide cases, I've only got one left. I'm not adding anymore, though I hate having the single loach I need to save room for Pneumy.