Researching Compatibility Before Purchase

Fish species vary widely in temperament, size, water parameter needs, and compatibility with other species — recommending a purchase without confirming compatibility with a customer’s existing tank setup risks real problems.

Territorial and Aggressive Species Considerations

Some fish species are genuinely territorial or aggressive and shouldn’t be combined with certain tankmates — a specialist should understand these patterns rather than assuming all fish coexist peacefully.

Understanding Adult Size, Not Just Size at Purchase

Many fish are sold small but grow substantially larger — recommending based on adult size and the customer’s actual tank capacity avoids a mismatch that emerges only after the fish has grown.

Water Parameter Compatibility Between Species

Different species can require genuinely different pH, temperature, or hardness ranges — combining incompatible species in a single tank creates an unsustainable situation for at least one of them.