Questions about my reef tank

Sorry to hear about your loss! It could be the tang. To know for sure, just sit back and watch. Can you block off part of the tank or put the yellow tang in QT/hospital/ timeout tank? Clowns become territorial not long after being placed in their new home but won't stand a chance against the tang by being so much smaller. Providing the clown with 'protection' should help. Is she eating? You will want to watch her tail doe any infection.

I'm not familiar with a grey starfish; are you sure it isn't white? If it's white and tiny, it's probably an asterna star. Although it's sometimes said that they will eat coral, I've never personally heard anyone having trouble with them. Good luck with your clown.

 

Hey Chappy

Not sure what may be nipping at the tail, it may not be nipping, it may be sick.

The small starfish are called Asterina Starfish. The usually just eat algae, but they may also eat Zoa's. You can try to pluck them out if you dont like them, or get a Harlequin shrimp, however you will have to get rid of the shrimp after the stars are gone as they will not eat anything else.

 

I'm surprised that the clowns are the ones showing stress over the corals or tang. How are other params in the nitrogen cycle (NH3, NO2, NO3)?

 

Here's a link that might help you out: http://www.wetwebmedia.com/clnfshdisart.htm And, welcome to GIRS!