Some plants that are non-toxic to humans may be toxic to fish or other aquatic species. For some people it’s common practice to drop plant cuttings from a grow bed into the water for the fish to eat. By having plants that are OK to grow in aquaponics but have leaves that are toxic to fish, there is a risk of inadvertently dropping toxic cuttings into the water and poisoning the system.
It would be advisable to not mix toxic to human houseplants with edible plants in the same grow bed as those unfamiliar with plants may inadvertently consume a poisonous plant.
Houseplants are often cited as being beneficial to a household’s air quality. NASA did a series of studies regarding this in the mid 80s and many recent reports regarding houseplants and air quality appear to refer to those reports. The plants studied by NASA where selected based upon local availability and low light requirements. They where not selected based upon some criteria where they where known to have exceptional air cleaning abilities. It can be assumed that a great many more plants are effective at cleaning the air, and that the list provided is not a conclusive list.
There is a note that the plants appear to be effective in cleaning the air not due to their leaves, but through their root system. http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930072988_1993072988.pdf (pg 10). How this applies to aquaponics is unknown, as the soil is removed but the bacterial presence is maintained.
Being that ‘the list’ is often referenced, lets explore this list in regards to plant toxicity to both humans and to an aquaponics system itself.