I had one about 6 months ago. I kept it in fresh water, but then I found out that they're more on the brackish side. He was with me for about a month. He seemed to be doing fine in fresh, but he just suddenly died. I don't think it was eating enough. I heard that they may only except live food (worms, feeders, etc.)
ya i have one i've had him for about 7 months im bad with time. but i pop feeders in every week and stuff i've never seen him eat but hes alive and heathy so hes eating something. so other info would be they get about 12in and are brackish to fresh and are slitly poisonous
If we are talking about the same fish there was a thread about it not too long ago, I will see if I can find it. Sort of an ugly lump of a fish? The most likely one is the three-spined toadfish (Batrachomoeus trispinosus), petsolutions sells them as freshwater lionfish ($20 @ 2-3 3/4"),the pics are of that one and are from fishbase and petsolutions. This fish gets to around a foot long and at that size can eat a fish almost as large, they are mildly venomous and have a sting about as painful as a wasp. There are other fish from the toadfish, scorpionfish, and even stonefish that are sometimes sold by that name, all can cause painful envenomations. Some are a bit smaller, all are predators. A few tolerate freshwater esp. when young but are better suited to brackish. This one does best with 2-3 teaspoons salt per gallon or it becomes vulnerable to disease and grows poorly.
it could be one of those saltwater fishes that are subjected to freshwater... poor creatures are forced to accept freshwater instead of saltwater by slowly adding freshwater (w/out salt) everyday.. until the fish is in total fresh water..
I kept one of these before in the past... had it housed in a Polypterus sp. tank. (with added salt). It did fine for the time that i kept... (7-8 months). Had it taking raw shrimp, earthworms/nightcrawlers, frozen/fd krill, live rosy reds, sinking pellets, and even algea wafers... ended up giving it away to a friend.