"Large water changes kill shrimp"
Use the complete answer. A verdict without its boundary and next action can become another myth.
What is supported
a change can expose animals to differences in temperature, dissolved composition, pH, contaminants and gas state.
What is not established
percentage alone does not determine safety, and a tiny change is not automatically useful or harmless.
What to do next
identify the purpose, compare source and tank water, calculate dilution and observe the result. Use the water-change guide.
Exact evidence trace
This is the selected claim-level trace, not every source used by the broader guide. Roles describe how each record is used here; they are not quality grades.
Evidence records
- limitation context Assessment of a biofilm-based culture system within zero water exchange on water quality and shrimp survival and growth: One defined zero-exchange culture system does not establish a universal water-change percentage.
- limitation context Efeito de compostos nitrogenados no camarão Neocaridina davidi e na rã Aquarana catesbeiana: An acute nitrogen experiment cannot make water-change percentage the sole safety variable.
Supporting authorities
- A Primer on Water Quality: Supports dissolved-material and evaporation context for replacement water.
- About Water Disinfection with Chlorine and Chloramine: Separates source-water disinfectant context from percentage alone.
Named open questions
- What chronic nitrate-only exposures affect Neocaridina across life stages? No controlled chronic nitrate-only Neocaridina experiment was located in the current review.
- What are chronic ammonia and nitrite no-effect ranges for Neocaridina? A direct N. davidi thesis provides a 96-hour acute juvenile experiment. An official abstract for a restricted 2007 N. denticulata thesis reports chronic total-ammonia growth and reproductive comparisons, but its complete methods and results are unavailable. Neither source establishes a chronic operating range, and no controlled chronic nitrite study was located.
- What GH, KH, pH and conductivity combinations are true biological optima? Field occurrences and study culture water describe places or reproducible conditions, not species-wide GH, KH, pH or conductivity optima.
Inspect the broader guide evidence dossier for all records, authorities, gaps, searches and changes connected to the practical guide.
Share the complete answer
Open the plain-text answer or open the original teaching card.
The detailed guide owns the evidence and limitations. Challenge this claim with a stable source if an important boundary is missing or stale.