If you’ve ever seen Finding Nemo, you’ll know that fish tanks can get right nasty very quickly if they are not well-cared for.
That said, there’s not a ton of specific guidance on this regard; even the CDC Guidelines for Environmental Infection Control in Health-Care Facilities uses no stronger dictate than “avoid” when it comes to fish tanks:
I. Controlling the Spread of Waterborne Microorganisms
- Practice hand hygiene to prevent the hand transfer of waterborne pathogens, and use barrier precautions (e.g., gloves) as defined by other guidelines (36,142–146). Category IA
- Eliminate contaminated water or fluid environmental reservoirs (e.g., in equipment or solutions) wherever possible (142,147). Category IB
- Clean and disinfect sinks and wash basins on a regular basis by using an EPA-registered product as set by facility policies. Category II
- Evaluate for possible environmental sources (e.g., potable water) of specimen contamination when waterborne microorganisms (e.g., NTM) of unlikely clinical importance are isolated from clinical cultures (e.g., specimens collected aseptically from sterile sites or, if postprocedural, colonization after use of tap water in patient care) (148–151). Category IB
- Avoid placing decorative fountains and fish tanks in patient-care areas; ensure disinfection and fountain maintenance if decorative fountains are used in public areas of the health-care facility (152). Category IB
When all is said and done, this clearly becomes the territory of the mighty risk assessment process. The location of the tanks, how immunocompromised your patients might be, etc. are all important considerations. And I suspect that it would be worthwhile figuring out exactly what would make a fish tank in a patient-care area “unavoidable.”
For instance, recognizing the calming effect of little fishies swimming around, you might not be able to have them in a pediatric oncology area; but going a bit further, if you can environmentally separate the fish tank from the area, the risks might at that point be outweighed by the benefits. It also wouldn’t be a bad idea to involve some physicians in the assessment process — your epidemiologist or even an oncologist would be a very authoritative “voice” to have in the discussion, particularly if you find yourself defending your position with those regulatory types.