Covariance measures the linear relationship between two variables. The covariance is similar to the correlation between two variables, however, they differ in the following ways: Correlation coefficients are standardized. Thus, a perfect linear relationship results in a coefficient of 1. The correlation measures both the strength and direction of the linear relationship between two variables.
The Largest True Goldfish Ever Caught. The largest true goldfish on record was measured at 5lbs (2.27 kilograms) and was caught by a 16 year old schoolboy in the UK. This blown-up goldfish was evidently a pet before it ended up into a lake.
Large aquariums are a definite requirement for their long-term care and survival, as goldfish can grow quite large, depending on the breed. The common goldfish, so popular on fairgrounds, are among the largest, and they are capable of reaching over 18 inches and 10 pounds. Even the smallest breeds can reach between 4 and 7 inches, making them more suitable for a 20-gallon or larger aquarium than a bowl.