Build a stocking plan—not a fake fish count.
Build the whole community — fish, inverts, plants, corals, with quantities — and get a deterministic assessment: adult-size bioload vs your filtered capacity, the temperature and pH window the whole list shares, schooling minimums, and tank floors. Every number shows its work; no AI, no inch-per-gallon.
Add species to build the list — schooling fish start at their minimum group size.
How the assessment works (and why it isn't inch-per-gallon)
Waste tracks body mass, not length: a fish's mass scales roughly with the cube of its adult length, adjusted for body shape, and its waste output follows metabolic scaling (mass0.75). We sum that across your full list at ADULT sizes and compare it to your tank's capacity, adjusted for realistic filter turnover. Inch-per-gallon calls one 10-inch oscar equal to ten 1-inch tetras; mass-based math correctly makes the oscar roughly twenty times the load.
When you're ready, use the AquaLens app to record the actual residents and water history that make a tank-specific review possible. Until then, leave margin and make every new addition earn its place in the plan.