After purging the apparent Box Flies that were eating the leaves, a sort of gall disease has effected one of the mangrove trees (is there a relatioinship?).
Could be Rhizophora or Cyindrocarpon gall.
The Rhizophora have denuded forests in West Africa, and Cylindrocarpon effected mangroves from Florida, to the Atrato rive in Colombia.
I wondered if the thick Dieffenbachia in my sump were depriving the Mangrove of enough nutrients (nitrate) to fight off the disease,, so I removed the dieffenbachia from the sump about a month ago.
The Diefenbachia in the tank itself remain, yet the sump is now free of them.
And the Mangrove seems to be recovering a "bit", time will tell
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