water testing

Distinguish water clarity from measured water conditions, understand why a photograph cannot confirm an aquarium's readiness and use clearly identified tests alongside observations rather than as interchangeable evidence.

Check a strip's actual parameters, handling instructions and reading scale, and distinguish a convenient result from a complete assessment of aquarium water or an automatic treatment decision.

Understand why biological filtration must become established, distinguish elapsed time from demonstrated readiness, and prepare a freshwater aquarium without using fish to test an unfinished system.