Oscars grow astonishingly fast, so it’s important that you understand what you are getting yourself into when you pick them up from the pet store or a Cichlid breeder. It’s said that Oscar fish can grow at a rate of 1 inch per month until they reach adulthood. If you don’t have an ideal Oscar fish tank size (55 Gallons+) then your fish’s health will be compromised and they will be at higher risk of disease and premature death.How big do Oscar fish get? It’s not uncommon for them to grow up to 14 inches. On average, they will be around 10 – 12 inches in length.
Oscar fish babies are as small as any other tropical fish when they are young (1 to 2 inches) but under the right conditions, they can grow at a rate of 1 inch per month, to a fully-grown size of around 10 – 12 inchesDue to their sheer size, it’s important that you have more than enough tank for the Oscar fish to grow into and thrive in. An Oscar Fish tank size should be no smaller than 55 gallon per fish to prevent putting any unnecessary stress on the fish.
Oscars are notoriously messy fish and require a lot more maintenance than most other species. Oscars produce a lot of waste so frequent water changes are a given necessity, but the smaller the tank that you house them in, the more frequently you will have to clean them and check the water parameters.