I quarantine all my new fish for a week or 2 before placing in my main tank. My quarantine is 10 gallons and I have read that it is not good to quarantine a blue hippo tang (Dory) due to the stress of it having to get resettled when put in the main tank. It eats good in quarantine but does hide out most of the time it sees someone walk by it. Any info on this? It has been in quarantine for a few days now, Thanks