spill the beans, where to they come from, what do they need to do well? does aquatic fungi need higher than atmoshperic CO2 or 02; or rotting nasties to consume?
i don't want to be the skeptic, but it looks like that might've been a random shroom from a dry start or something that just got submerged. which to me makes sense of why it looks like it is pearling... It should not pearl, it is not a plant. it contains no chlorophyll.