Are you gutloading the ghost shrimp before feeding out. This will help variy thier diet. but letting the ghost shrimp eat, the horses are in getting the extras they need.
here are a few things
Good products to use for enrichment include a HUFA such as Selco, Super Selco, or AlgaMac-3050, an Astaxanthin containing product like NatuRose or PhytoPlan, and Beta Glucan an immune system booster. (Note: Tahitian Algae Paste can be used in place of several of these products as it already contains them as ingredients). can also use cyclops, even good quality flake, if the ghosts will eat it.
You can also stock your tank with live mysis and amphipods. Have you tried switching them to frozen?
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