Yep, when RTN starts, the best thing to do is cut well above the damage and pull out the remaining parts. Sometimes you can save a piece, sometimes not.
Was the ammonia spike the result of the fish dying or did that cause the fish to pass? If so, were you able to identify the cause of the ammonia?
A good water change doesn't hurt either, to help prevent any other corals from following the same trend.
I have not had the best luck either from getting one to stop once the tissue starts coming off. Fraging is the best option if its a large coral and you can cut the frag off at a fairly good distance from the RTN that might be your best bet.
On one occasion I had a good size stag acro that RTN and almost died except for the tips. After about 6 months of growth the colony has almost made a comeback.
Of course I really increased my water changes and kept my husbandry habits more stable and I think that was the trick.
the amonia was a stupid mistack . i combined my two tanks and didnt have a cleaning crew in the second tank and then added two new fish and one fish wouldnt eat so i started giveing him mices shrimp and stupidly dident think of the shrimp the fish didnt eat . prob. wont be the last stuped thing i do but i do .feel bad about the bad husbandry.i will flog myself latter
