Start with your water
Measure the water you will actually use: pH, general hardness (GH) and temperature. A tap-water reading is a starting point; check the established aquarium as well. Choose a species and source that fit conditions you can maintain. The species profiles distinguish our aquarium planning targets from reported wild conditions. Do not chase an extreme pH just because a fish has been collected there. Ask the breeder what the actual fish has been living and feeding in.
Floor space is the useful space
Volume helps dilute waste, but it does not tell you how much bottom territory is available. A tall, narrow tank can hold plenty of water while leaving little room for a fish to escape another. Our Finder therefore asks for both volume and base dimensions. Use the minimum as a screening rule, then account for the number of fish, layout and breeding intention. A minimum for one carefully managed arrangement is not a stocking formula.
Make shelter work
Combine fine substrate, wood and suitable covered retreats. Inspect the layout at fish height: can an individual leave one shelter without crossing the same open territory every time? Spread hiding places across the aquarium and interrupt sightlines. Check that decorations cannot trap fish. Dense planting is useful only if it leaves accessible feeding and maintenance areas. A fish pinned behind a filter has not found a successful territory.
Establish the routine before stocking
Use a biologically established, filtered aquarium and verify that ammonia and nitrite are not accumulating before adding fish. Keep replacement water consistent and test whenever behavior changes. Maintenance frequency must follow the actual stocking and water quality, not a fixed percentage copied from another aquarium. Remove uneaten food, observe every fish and investigate sustained hiding or loss of appetite.
Choose companions deliberately
Start with the purpose of the aquarium. A display with peaceful upper-water fish and a breeding aquarium have different needs. Other bottom-territory fish can create conflict; shrimp and fry may become prey. A pair can stop being compatible when spawning begins. Keep a realistic separation option, and reconsider stocking when one fish repeatedly loses access to food or cover.
Further reading
Read species-specific sources alongside the profiles. This guide provides practical planning advice, not a universal recipe for every population.