Yes these originally can from COTA imported into the UK by Rob at Lincs fish. There currently in a 6.5ft 200uk gal tank. You should get away with a group of small growouts in a 90gal, then when a pair develops they will need the entire tank to themselves. Gravel or sand it's just a matter of choice. They will dig around happily in ever. As for food and water there not fussy at all. Any quality pellet will do, and a good water change schedule. Good luck thea beautiful fish to keep, I'm sure you'll not be disappointed.
I'll try to get some update pics later. I've now had mine 1 year.