It depends completely on what kind of fish you are keeping in it. Generally fish that are more colorful need warmer water, around 80'F.Fish that are more plain in color like goldfish need water about 70-72'F.
if there is a black out and you do have a fish tank you should be fine an less you have a chinease fish or any fish that is in the red mark for fish
You should change the water in your fish tank every 1-2 weeks to maintain a healthy environment for your fish.
The charcoal filter in a fish tank should be changed every 2-4 weeks to maintain water quality and keep the tank clean for the fish.
You should have it running for about 2-3 days before putting fish in your tank.
Water, for starters.
Both fish, and fish tanks, come in different sizes. So the number of fish that ideally should be in a tank, depends. Somewhere between one and a hundred would be normal.
Not unless you had another fish in there.
Salt Water Fish
IN WATER!!!! (TANK!!)
You should change the water in a fish tank regularly, typically every 1-2 weeks, to maintain a clean and healthy environment for the fish.
It means the tank should be cleaned.
The mass of a fish tank should be measured in kilograms.