Hi Caryl,
Thanks for reply, the only thing I add as they are both in with Cory’s is declorinator, and then only in small amounts as I prefer the aging method for water.
The reason they were both together was in lockdown, I medicated them together to try to eliminate the issue. But that was now 6 months or so ago since they were seperated again. No big surprised they used the opportunity to spawn, which is how I have come to the conclusion its a parasite. As none of the fry exihibited the issue until they hit 6cm or so.
In all my research and reading I didn’t see the exoskelton fact, that explains alot as they sure are tough little buggers ?. So thanks for that, the more information the better.