How fastdo they really grow wut do u feed ur guys oscar to make em grow big

with good tank size, good water parameters, and good
feedings, oscar grows at an average of 1 inch per month
for the first 12 months. once matured, they grow slowly
but become bulky, develope the lumps on the shoulder and
become thicker.

I see well his tank is good water is being checked everyohter day I'm feeding him cichlid pelets ( hikari cichlid gold) and the occasionl feeder gup

in a average year an oscar will grow to between 7-11 inches in length. keep in mind however that when you purchase your oscar he is probably around 2-3 months old at the time.

as for feeding vary their diet with an assortment of foods. always use a quality pellet as a staple and add things like earthworms mealworms shrimp krill silverfish and beefhearts to name a few. this will help ensure a healthy and contented oscar. also to promote growth be sure to have an adequate tank and proper water quality at all times.

hope this helps

giving guppies will tend to make your o aggressive to other
specie. moreover, if you are not sure of the source, it may
lead you to parasite contamination..... so if not needed,
refrain from giving guppies or feeders.