Substrate for Northerns - Topsoil and Playsand

[EverydayThor]

Hi everybody,

I'd like to try a blend of organic topsoil and play sand for one of my Northern BTS. The recommendation (Reptifiles and Clint's Reptiles) is a mix of 60:40 topsoil to play sand.
My question is now... is that by weight or by volume? Topsoil is sold in liters, sand by the kg.

My enclosure is 5ft x 2ft and substrate depth should be 4-6in. If I go by volume, I'll need to fill approx 2ish inches with sand (for calculations sake)... that is around 140lbs / 70kgs only for the sand... That seems a bit extreme to me?!
Going by weight would add up to 35kg/70lbs for the soil and 23kg/50lbs of sand. Still very heavy with >50kg/100lbs but significantly less than the >100kg/200lbs of the first calculation.
But since the difference is so significant, I wanted to make sure I don't provide a substrate that is completely "off"...

Did anybody try a similar blend? Would be glad to get some directions here.
Thanks a lot
Thor

[rixusaku]

Pretty sure they mean percentage, so volume. 60:40 topsoil to play sand would be 60% of the mixture being topsoil and 40% of the mixture being play sand. The ratio works whether you're filling a three inch square or your pool.

Now, how much of it you need to fill your enclosure adequately, you're going to have to either math out or do some guess testing. Either way, whatever you fill, it will be filled with a mixture of 60% topsoil and 40% play sand.