Cabomba pondweed - an effective (and legal!) alternative
You'll already know that Cabomba pondweed, used for the 'bubbling pondweed' photosynthesis practical, is in the position of being phased out in the UK and EU. This is because it is a potentially invasive non-native species in Europe, and more stringent rules on invasive non-native species have come into force. While it is still intermittantly available, we are looking for alternatives.
We are currently recommending Hornwort and Egeria densa as possible alternatives. They bubble less dramatically than Cabomba, but a warm environment (e.g. beaker of warm rather than cold water) and under bright light will still allow this practical to be carried out.