Building new planted tank.

[RTR]

As tanks commonly are named after their nominal volumes, perhaps the first thing new hobbyists need to learn is that tank nominal volumes are worthless other than as labels. Operating volumes are always substantially less than the nominal volume. Operating volume are important numbers that we use routinely. A 50% water change is one half the operating volume. Hobbyists must not confuse labels with reality. The differences are not trivial.

HTH

[J-P]

+1

When I measure tank volume, after substrate and decor. I subtract 30%. A 100 gallon tank would roughly hold about 70 gallons of water. It isn't exact, but I have had much success using this equation.

[Iliveinazoo]

We use tank sizes all of the time and I would argue that labels are important and not to be ignored. I am in the fishkeeping hobby and therefore can be deemed a proud "hobbyist". If I was to go out and buy a fish tank I would look at the "minimum tank size requirements" for a fish and I would buy a tank that met those requirements as a minimum, I would not ask the aquatics retailer to measure the inside tank dimensions and work out a rough volume before calculating the water displacement of my chosen substrate and, maybe, stone buddha. Why complicate things when you don't have to?

To the OP: I would go for a densely planted DP tank with some Caridina japonica and hope that a colony would survive among the plants and moss.

[RTR]

Using labels as labels is fine. Using them for calculation is a grave and potentially dangerous to fatal mistake. Concentrations need to be reality-based, not label based.