Hi, I had a SAlungfish for 5 years til he sadly died. I've recently picked two more juvies, the same size as yours, beautifully golden-spotted. I also placed them in a 10 gallon for their quarantine. SALs are endemic here in Argentina -where I live- easy to come by and very cheap: I bought two for U$ 8!
Regarding the former I had, it was not easy in the beginning. Extremely shy, he hid all day and night. He didn´t eat anything at all for three (yes, 3) months! I was absolutely sure it'd die. I kept on offering differente stuff to no avail. Checked parameters and tried everything, from water conditioning to even leaving him all by his own for a fortnight. I even introduced a dragonfly larva and didn't see it for days, only to find a beautiful adult dragonfly in the room, a carcass on a stone in the tank, and a SAL exhibiting a damaged tail, as if cut with a scoop. Eventually he started eating out of the blue, and from that moment on, everything was good to him: beefheart, floating flakes, bottom fish food, dead feeder fish that remained in the bottom, garden snails and slugs -chunked or not- , earth worms, bloodworms, cat food, and even a pretty goldfish which was in no way intended to be a feeder fish.
Those almost five years he shared the tank with a Hipostomus plecostomus, and some guppies or platys. He never attacked anything. When they died, they'd be gulped down in minutes. He never had a filter or an aireation system and lived perfectly happy. I did frequent water changes, though, for the water gets fouled very quickly when they are confident and eat a lot.
The problem came when I moved him to a bigger tank -he had reached 2,5 feet. Being it bigger, I added aireation and a filter. The SAL was restless all the time, poking his head everywhere. I thought he was happy. He would come up for air more frequently and ate a lot, but was almost never at rest.
The lid had a very small breach in it. Enough for the SAL. On day 8 in his new tank he jumped out. I found him the following morning, dry as leather, but alive. Its agony lasted nearly two more months, shedding skin all the time and eating nothing. At the time I myself fell ill and was admitted to hospital for 15 days, only to find muy pet gone when I was back. Had I stayed home maybe I could've done something else, but it was beyond my decision.
Hope to be luckier this time with the new pair.
I expect this information has been helpful to you. SALs maybe the least active of all lungfish and spend the daytime hiding behind a rock or coiled up around some log. They're very interesting even so. And can get really tame. Confinement doesn´t seem to bother them as long as they can stretch all the way and have a little stroll.
