Although, if you have had those shrimp in there for much more than a year, they may have been reproducing their numbers in a sort of an equilibrium. A year old glass shrimp is an old one.

As an aside, I was privileged to have Scott and Reza visit about a month ago. (I do wish the fishroom were in less disarray. They were very gracious.) They looked at a couple of tanks where the plant mass was several 100 times that of the few fish in there. Scott turned to Reza and noted, "Maybe we don't have to thin that tank out."

I think that many aquarists have had fish like zebra danios spawn in their community aquariums. Danios will scatter more eggs than livebearers will drop fry. That works in nature. In the close confines of a community tank, both the Danios, certainly the Corys, and maybe everybody else, got a snack.