Substrate (gravel) How much to use?

[MrDaytona]

This may sound like a question that everyone knows the answer to but:

How much gravel is recommended for each tank?

Is the proper amount determined by the number of inches that covers the bottom of the tank?
For example - two inches of gravel across the entire bottom.

OR

Is a better rule of thumb being X pounds of gravel for every gallon of water in the tank?

I realize that there are variables such as ; What type of filter is being used? - Will you have plants in the tank? - How large is the tank? etc.?

In my case - I'll be using an undergravel and a wet-dry filter, have plants in the tank, with a large piece of driftwood, and assorted fish.
When I asked this question at my LFS the answer was = One pound of gravel for each gallon of water. Is this correct or not?

I may have to have a dump truck deliver 400 lbs of pea gravel, which I will then have to wash, to place in my 400 gallon tank.

I am wondering what are your thoughts in reference to this basic question?

As always thanks for your input -

 

[Devilishturtles]

Mr.D, I believe that your LFS was correct. The standard reccomended gravel is 1 pound per gallon of water. This puts about a 1-2 inch covering of gravel on the bottom of your tank. I am wondering though, if since you will be running an undergravel filter, if you should go with a tad less. I'm not really sure, never had a undergravel filter. So good luck with your tank, hope I helped a little

 

[jsoong]

I think you need a bit more for UGF - like 2-3".

Best to buy by volume. Measure your tank "footprint" & multiple by depth of gravel. Eg. for a 4 foot by 2 foot tank & gravel depth of 3 inches, you need 48x24x3 = 3456 cu inches = 15 gal = 2 cubic feet.

If you're getting pea gravel, just go to your garden/landscape supply place. They sell it by the cubic feet.

 

[newtankgirl]

if you want to have any live plants, you are supposed to have 2" for them to root proplerly. I have fake plants, but I still have the required 2", that's what my lfs told me too.

 

[TankGirl]

For live plants you will need at least 2", but preferably more. Live plants and UG filters don't necessarily go together, if you can skip the UGF.

AA has a handy calculator (http://www.aquariumadvice.com/calcs_new.php) for sand bed depth, which is the one you need.