Along with several other methods I've done this twice going with MGOCPM, miracle grow organic choice potting mix (dirt).
The first tank is 2 years old and the new one is just over a month wet.
Copied from one of my threads;
More people seem to be deciding on dirt tanks rather than waiting for the soil to be mineralized, or going with dosing EI, high light and CO2 lately. I think this is cool
Hopefully most are reading enough information first and thinking it through.
Two HUGE considerations doing this.
Using 'natural' soils READ the contents on your bag of dirt! I know it contains dirt,,, (duh),,,
but NO COW POO! Small amounts of chicken poo can work but no! no! moo! moo!
Also remember PLZ that while natural tanks (dirt base) and seeded filters can be stocked from day one go lightly with your first stocking list. Dirt goes through changes going from dry to saturated (submerged) and the rate of break down on the organics changes too. Sometimes it can be more than the tank and fish can handle.
For the first couple of months whether you want to or not test your water. Every couple of days and be ready to change it if the soil burps (it can happen). You might have a tank like mine that ran straight through the issues quickly and was trouble free from then on. Lots of plants (including floaters), no hard scape to trap the soil gases, control the light (a big key to dodging algae), watch things and let the tank settle (month maybe two). The capping material needs to be small enough to contain the soil yet allow the gas exchange to occur.
That's the first trade off for not waiting for the dirt to finish the mineralization process. Attention starting out, more or less high maintenance in the beginning., Things can get busy if a bump in water parameters occurs. All the organic material and the bacteria that chew through it do give you free CO2 for a period of time.
The second major trade off you make is that rooted plants are there to stay. Removing plants with a good root structure is a HUGE PITA. I had an Amazon Sword that had to go. Cutting around the root ball directly under it I killed the plant taking it out and left all the root runners in place. Thinning a field of crypts means a water change and repairing the cap adding more material. Soil tanks are a set it and forget it type of tanking (imo). If you like to change things around, re-scape, swap out plants then NPT is not for you. If you want to top off the tank when the water gets low, trim to make room for the fish to swim and not dose for months it might be what your looking for.
My first tank burped a couple of times and I pulled the fish once worried about water quality but the second has been smooth, I added clay, sand and potash to the mix so far so good.
Both threads include parameter test results, water change volumes, and pics following the time line on the tanks if your interested in wasting a few minutes.
The oldest. Gets boring after a few pages as the tank settles in and things go on autopilot.
Better pictures on the sub build but only a month old.
Dirt layering starts at the bottom of page #1.
Hope you start a dirt tank and journal
and hope there's helpful info for you in the threads.