Adrian Slack advocates: "The whole potted plant [S. psittacenia] should
be completely immersed in clear soft water during the whole winter, so
that its foliage is entirely submerged".
I know from experience that this is not a requirement for growing
S. psittacenia. However, if the "lobster trap" type trapping
mechanism works primarily under water (as Slack describes), then this
species at least, does not suffer from retarded gas exchange.
Dropping an aquarium aerator in the bucket might be a good precaution,
anyway. Most CP growers have an old aerator around. We were eyeing
an alternate use for the aquarium even before the last fish died! :-)
Michael