ACRO RTN, what are the likely causes?

[seaguy7]

Here's a pic of a couple new acros I bought. Within about 3 days of arriving, they had necrosis. It does not appear to have spread over the last 4 days (I got them a week ago).

I have searched many many threads looking for possible causes/solutions but haven't been able to figure it out. It may be red bugs or AEFW but I can't see either. I have a couple older acros that are still fine but have read the horror stories of problems like this spreading.

I've just tested Nitrates (not measurable), Ammonia (not measurable -- both these are aquarium pharmaceutical tests) Phospates (0 -- salifert test, I am running rowaphos). SG 1.024, Temp 78-80, pH 8.16 (drops as low as 8.06 at night). KH is around 9, Calcium almost 400 (both Salifert tests). A possibly related odd occurence is that my Chaeto in my sump has actually shrunk over the last week. I have almost zero algae growth in the tank and a SSB.

Any ideas?


-Greg

 

[cward]

I would pull the acro in the second picture out of the tank and look for AEFW eggs. You could also put the coral in a bowl of saltwater and swirl it around to see if any pests fall off. It helps to have a magnifying glass to look for the eggs, which will look like a cluster of small brown spots.

 

[seaguy7]

I took out the one piece, blasted it with a baster, examined it with a magnifying glass, and still could not see anything that looked suspicious. I ended up cutting off the two limbs with dead pieces and fragging the tips that still look healthy.

I still have no idea what caused it. I guess I'll know soon if it spreads or recovers.


-Greg