Aquaculture Simulator is a management simulation in which the player operates an indoor recirculating aquaculture facility. Two parallel economies run in the same hall: rainbow trout are raised to weight and sold by the kilogram for thin but predictable margins, while koi are valued by grade based on pattern, colour and body conformation. A young koi does not reveal its final quality. The game presents a range of possible outcomes that narrows as the fish matures, forcing the player to decide whether an animal is worth feeding for up to two years before its value is known. Fish consume feed daily, so keeping low grade stock erodes profit. Water chemistry underpins both operations. Oxygen must be held within a corridor, as insufficient levels suffocate fish while excessive levels cause gas bubble disease. Ammonia rises with overfeeding, and a single temperature control separates the two species. Customer orders arrive as email on an in game terminal with a calendar and banking application, and missed pickup dates cost both money and reputation.