OK, just read your other post. You treated with copper even though there was no evidence of ICH. Time to stop listening to the LFS
Keep them there for 30 days! STOP the cupramine treatment.
Are there any fish left in the display tank?
Do they show any signs of stress or disease?
Keep doing pwcs in the DT and QT tanks to maintain stable parameters. If the tang is still alive trade it back to the lfs
for something more suitable for your tank.
SLOW down on the livestock additions. Add only 1 or 2 fish per month (30 days apart).
Seymour's Salt Water tank rules:
Rule # 1. Nothing Good ever happens Fast in a salt water aquarium
Rule # 2. Don't add anything (supplements/chemicals/minerals)you don't test for first.
Rule # 3. PWC
(Partial Water Changes) are your friend, and cure many ills.
Rule # 4. QT EVERYTHING before adding it to your tank (mandarins excepted, corals should be dipped)
Rule # 5. Use only RO
water (either buy it or make it)
Rule # 6. All animal species live longer on a 30% reduced caloric intake. Only feed every other day at most (fish species dependant)
Rule # 7. Hyposalinity is the best, safest, and most effective treatment for marine Ich (IMHO
Rule # 8. A Refractometer is a MUST HAVE, not a luxury.
Rule # 9. Anemones will never live anywhere near their normal (aprox 30 years) lifespan in a home aquarium. Leave them in the ocean.