Shorah, Welcome aboard!
Fellow pellet researcher here! Speaking primarily about my own experiments and test results here, and may not necessarily reflect other people's results when testing.
I've done experiments of my own on the pellets, trying to figure out if there was a missing ingredient or a way to improve the efficacy of the pellets. I've ground them up, cut them up, tried mixing my own batches based on the elements present in Er'cana... I've shoved 'em whole sale through vacuum tubes on a timed delivery mechanism, even... Nothing really seemed to help matters, much.
My attempts at recreating the pellets themselves outside of Er'cana have not gone anywhere well, unfortunately. The issue may be I just am missing something, or that the facility has some portion of the process black boxed and I'm unable to recreate that process externally, and I'm not entirely sure which it is.
I've tried various mixtures of elements present in the age, ranging from samples of the stalk plants to what I and others have theorized to be plant seeds disguised as rocks (Though, that makes them hard to differentiate FROM rocks, as my last blender can attest to. RIP Smoothie Master 2.8), as well as taking elements of the local water as potential sources for food processing.
All of it has either been as effective as a poorly made pellet, or non effective at all. In that, I suppose my efforts aren't too bad- though I should be thankful I haven't had an experiment explode in my face yet like some pellets have been known to do.
Unfortunately, figuring out what the heck the Pellets are has been just as... well. Unfruitful. Chemical analysis of the pellets has been as frustratingly obtuse as much as DNA tests of the Algae itself have been. I honestly haven't been able to get any coherent results from either. I'm honestly beginning to suspect that the whole Lake Ecosystem is reliant on some element foreign to Earth that I can't identify in Er'cana.
You're welcome to give it a try and see if you can do better than I can on the analysis front, though. I'd also wait to see if anyone else wants to chime in on the matter.
On an unrelated note, I'm happy to hear you found the sound system alright!
