4 cups per quart: 4 quarts per gallon makes 16 cups per gallon. So 16 x 55 is your answer.
It depends on the brand of "Salt MIX" Look on the package it should have directions.
Usually its around 45 lbs.
depends on the size of the fish, the filtration, if it is salt or fresh... lots of variables. A very rough estimate has always been 1 inch of fish per gallon of water.
3.47 cups
That is about 15.6 cups
About 1.9 cups
That is about 47 cups
About 2.236 cups
There are approximately 2 cups per pound in material like salt. So you are talking about 6 1/4 cups.
About 1.8 cups
That is approximately 1.333 cups
That is about 9.6 cups
You are talking about salt water (marine) fish. Maybe you should ask on the "salt water" category.
That is approximately 1.884 cups