How can you change the gravel on a fish tank ?

Do i just take the water and fishes out than just change the gravel? would it affect my fishes because the new gravel is not gonna have any good bacteria. and how many inches of gravel do you need for a planted tank?

How can you change the gravel on a fish tank ?
I'm going on the assumption that you don't have an extra tank lying around for the fish to be in for a week. but what you can do is this. take all the ornaments out of the tank and just put them on a towel. net your fish and put them in some sort of short term temporary holding with some of your tanks water for them in it. i would seriously recommend leaving as much of the water in the tank as possible. scoop out all the gravel with whatever. when it gets down to only a little left you can just use your hands. then put your new rocks in there. and thats it. 3 things.

1. Keep as much of the same water in the tank

2. Dont wash of the tank ornaments

3. Dont change your filter, do it at a time when its not gonna be filthy.

i would say do this maybe 4 or 5 days to at most a week after doing a normal tank cleaning/water change and filter change.

that way you give everything time to settle and grow strong bacteria. if you keep as much water as possible, dont clean the rocks and dont clean/change/replace your filter you should have plenty of bacteria in your filter, and some on your tank ornaments, to keep your tank from cycling again. and then the rock replacement shouldnt stress your fish out that much. oh and one more thing, wash the rocks... i'm sure you were going to, but i just had to say it, just in case. lol. and also freshwater aquarium salt helps keep stress levels down. good luck.
Reply:You can also take out a little bit at a time and change it. This take more time but, you will not have to take the fish out and store them it a temp home. Start at one end of the tank and change it by 1/8 every few days. This helps with the intrusion factor for the fish... Make sure you add i table spoon of salt for every ten gallons, this will help with stress levels..
Reply:if you can save as much of the old water as possible, try to do that. then just put your fish into a container with a bubbler (or a filter if you can) and put your pre-rinsed gravel into the cleaned out tank. i would suggest about 1 1/2 -2" of gravel for plants. that way you dont have to worry about them becoming uprooted easily.
Reply:take the fish and the gravel out leave the water there leave the tank to stand for 1 week, it wont effect the fish if you leave the tank to stand for 7 days,. as much as you need to bury your plants. hope this helped xx