Thank you! The CPDs are well on the whole and the juveniles are coming on really nicely. Once we do eventually move, I'd like to breed some more but don't fancy moving tiny fry if we are able to move at short notice. Just can't work out what these lesions are or what's triggering them, especially as it appears to be species-specific. I won't be buying anymore, but I wouldn't consider them to "not be working" as I've lost one after 6 months of no issues and none of the juveniles have shown any issues.
Live cultures are another one that's waiting until we move. I had a "daphnia jar" a few years back that was handy, but just don't have the space in the current flat. It's actually the reason why I added all the cherry shrimp though, they're a nice addition in general, but provide a constant live food source for the badis, along with smaller snails.
I did think about minnows a while back, they're beautiful fish! Their preferred temps are a bit low for my cryptocorynes though as far as I'm aware, and those make up the majority of my plants. I'd like another larger tank (again after we move) that I can have a bit warmer and then run this tank a bit cooler for the badis, CPDs, cherries, and corys, so if the CPDs do dwindle over the coming years then minnows will be right up there on my list of replacements
They were also top on my list for a loose Taiwanese biotope (they've been introduced to some areas of Taiwan) - do you happen to know if they're jumpers?