substrate math questions

[Gem915]

Hello all!

Getting back into having crabbies after a 10+ year hiatus. I'm getting my new tank tomorrow (20 gallon long). I've read the info about the ratio of sand to eco earth, but I wanted to make sure that I had my math right on the amounts.

I'm getting a 20 gallon long tank and I'm looking for about 6 inches of substrate. With the 5:1 ratio that means I should need about 100 lbs of sand and two bricks of eco earth? I'm using the info on the substrate guide that says that 10 lbs of sand fills approx 1 gallon of space.

Sorry, math has never been my strong suit!

[myllkti]

Yup that sounds about right If you’re a bit off somehow that’s not a big deal either, so don’t stress out about it

[Gem915]

Yup that sounds about right If you’re a bit off somehow that’s not a big deal either, so don’t stress out about it

Thanks! Just wanted to check cause 100 lbs is a lot!

[JTKermie]

I wonder how accurate the weight is on the bags of sand. Reason I ask is, I recently setup my 29g, which is the same 30"x12" footprint as the 20 long, just taller. With two 50lb bags of play sand and eco earth (5:1 ratio) and some crushed oyster shells and worm castings added, my substrate depth is 10". More than half the height of the tank. If I added the 150lbs of sand like you often see recommended for a 29g, I wound't have much space left.

[wodesorel]

I used three 50 lb bags of sand on my 29 and came out to about 7 inches, no EE. Tamping it down helps get a better idea of depth as it will settle tight over time.