Sorry to hear about your chocolate chip star........I am not sure if it was just a coincidence that the chip died the same night as the first night you had the brittle star.
What size tank do you have and how much rock?
Both of those starfish are carnivores as compared to Linckia or Fromia stars which graze. Of course with sensitive corals you have to be careful.
I was concerned about my orange star I have, cause I just bought another seastar to go with my orange linckia today at petco, an awesome red star fromia sp for $9.99...they had an awesome silver dollar size chip star for $5.99 sorry I didn't get it for you.
50 gallon saltwater fish only...1 mated pair yellowtail damsels, neon dottyback, tomato clown, huma trigger, lemonpeel angel, 12 stripe wrase, bi-color blenny, dozen or so hermit crabs-scarlet and mexican, cerith snails, turbo snails, orange linkia starfish, 50 plus pounds of purple-pink coraline encrusted rock and a few mushrooms.
Redsea prism protein skimmer, 404 Fluval, UGF
with two 201 powerheads.
7 gallon tank with 6 pounds of live rock and countless brittlestars, 5 hermit crabs, snails and 1 False Percula Clown fish and Camel Back Dancing shrimp