Try an aquarium calculator to determine how much substrate, gravel, or sand you need

https://fish-tank-volume-calculatorrjfn555.huicopper.com/ten-things-you-ve-learned-in-kindergarden-they-ll-help-you-understand-fish-tank-litre-calculator

Try an aquarium calculator to find out how much substrate, gravel, or sand you need. Get useful estimates based upon depth and tank measurements.