I would like to run some experiments on red algae fertilization (in class Florideophyceae). However, these experiments will be outside of the season where reproductive gametophytes are available in the environment. I would like to collect some gametophytes from the wild and keep them in culture until experiments (2-3 months). Any tips? How can I ensure that the male gametophytes will not release their spermatia before I am ready?