Gravel

it depends on how big the bags are and if you are going planted or not........
 
also depends on how deep you want the gravel bed to be
 
I just read the bag my gravel came in, and it says about 2 lbs. per gallon, but that can be taken with a grain of salt. Some people recommend only using 1/4 inch bottom gravel. I have a 24" x 12", and half of a 25 lb. bag was plenty, maybe 1.5" inch depth on average..
 
buy 2 30 pound bags and pour untill it looks right
its not an important aspect to the tank like a heater or filter (untill you go planted) its more for decoration

it depends on the geometry of your tank obviously a long tank will take more than a high tank

it depends on how layze you are cuz its esier to clean a smaller bed

it depends on what critters you have bacause some dont fell comfortable with glass bottom and some like to dig/move the deep gravel

also something to consider most fish prefer sand to gravel and sand is alot esier to clean because theres no cracks for the poops and stuff to sink into so it all sits on top

so buy two 30 pound bags and pour untill you fell its ready
 
I usually shoot for around 1 lb gravel per gal of water.
 
May I suggest pool filter sand? About $10 for a 50lb bag, and although it doesn't provide any nutrients like gravel, it looks alot better and is a better plant substrate.
Jake
 
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