{"topic_id":"exotic_aquarium_fish_husbandry","category":"exotic-pet-health","context":"---\ntopic_id: exotic_aquarium_fish_husbandry\ncategory: exotic-pet-health\ntitle: \"Aquarium-fish husbandry — nitrogen cycle & biofilter make water quality the central health axis\"\nlang: en\nsource: \"Merck Veterinary Manual (merckvetmanual.com) — non-Open-Access; paraphrased derived fact summary per COPYRIGHT_POLICY §3.\"\nsource_file: pdf-raw/exotic-health/mvm_fish_management.txt\ndate_parsed: 2026-07-28\ntokens_estimated: 220\nverified: true\nverification:\n  method: paraphrase\n  claims: 3\n  passed: 3\n  date: 2026-08-04\nsource_document: \"Merck Veterinary Manual (professional veterinary reference)\"\ncitation:\n  authority: \"Merck Veterinary Manual\"\n  title: \"Aquarium-fish husbandry — nitrogen cycle & biofilter make water quality the central health axis\"\n  url: \"https://www.merckvetmanual.com/exotic-and-laboratory-animals/aquarium-fish/management-of-aquarium-fish\"\n  retrieved: \"2026-07-28\"\n  ref: \"\"\n  doc_type: \"professional veterinary reference\"\n  needs_review: false\nlicense: paraphrase\ncopyright_note: \"Source Merck Veterinary Manual (merckvetmanual.com) is © Merck & Co., Inc. and not openly licensed; per COPYRIGHT_POLICY §3 all claims are paraphrased derived fact summaries (numbers and proper nouns preserved, sentences rewritten), not verbatim quotations.\"\nauthority_tier: T3\nauthority_tier_basis: \"T3:vet-ref\"\nauthority_tier_date: 2026-08-04\n---\n# Aquarium-fish husbandry\n\nSource: Merck Veterinary Manual (merckvetmanual.com), a copyrighted professional veterinary reference. Per COPYRIGHT_POLICY §3, the points below are paraphrased derived fact summaries: numerical values and proper nouns are preserved from the source, but sentences are rewritten and not quoted verbatim.\n\n## Claims\n\n*[Paraphrased derived summary — non-Open-Access source.]* Beneficial nitrifying bacteria live in the aquarium biofilter.\n*[Paraphrased derived summary — non-Open-Access source.]* When a tank is set up or disturbed, a temporary rise in ammonia and nitrite is expected.\n*[Paraphrased derived summary — non-Open-Access source.]* Ammonia and nitrite should be tested until measurable levels fall.\n","sources":["exotic-pet-health — Aquarium-fish husbandry — nitrogen cycle & biofilter make water quality the central health axis (retrieved 2026-07-28)"],"source":{"authority":"exotic-pet-health","title":"Aquarium-fish husbandry — nitrogen cycle & biofilter make water quality the central health axis","url":"https://www.merckvetmanual.com/exotic-and-laboratory-animals/aquarium-fish/management-of-aquarium-fish","retrieved":"2026-07-28","ref":"","doc_type":"official PDF","source_document":"Merck Veterinary Manual (professional veterinary reference)","verification_file":"pdf-raw/exotic-health/mvm_fish_management.txt"},"source_document":"Merck Veterinary Manual (professional veterinary reference)","source_file":"pdf-raw/exotic-health/mvm_fish_management.txt","trust":{"authority_tier":"T3","fidelity":"paraphrase","license":"paraphrase","display_grade":"B"},"tokens_estimated":220,"generated_at":null,"tip":"Use /api/v1/topics to discover more topics. /api/v1/nutrient for precise single-point queries. /api/v1/cross_compare for 2-3 standard comparisons."}