Coral tips, flesh disappearing?

[ludnix]

I'm having a strange issue I'm unable to diagnose. The tips on various SPS corals in my tank are having the flesh disappear. I cannot see any bugs or nudibranchs and none of my fish are picking at them.

Does this look like anything familiar to anyone?









Parameters:
Ca: 400ppm
Alk: 8dkh
Mg: 1500ppm
No4: <10ppm
pH: 8.0

I did a 10% water change on my tank a few days ago and am preparing another. I started running carbon as well.

It doesn't seem to be a flow or lighting issue as it happens in both my frag tank and display, which share the same water. I only use RO/DI water for making salt and top off which is testing at 0 TDS.

 

[ludnix]

Any ideas? It's occurring randomly on the top side of various coral's tips. It doesn't appear to be RTN, it's not spreading along the bleached tips as much as it's just appearing in new blotches all over the tips.

 

[pugbreath13]

I had this happen before when my ATO with Kalk did not shut off. But, by the looks of your Cal and alk this is not the problem. Did you recently add supplements? Your mag seems a little high.

 

[ludnix]

I tried raising my mag about a month ago using BRS mag to get rid of some bryopsis in my frag tank (which did not work) but nothing else recently. I've only done one waterchange since then so it's still a bit high.

 

[pugbreath13]

Check your salinity. After I used a similar product to raise my mag for the same reason my salinity went from 1.026 to 1.030. I didnt do anything else during this time so I blamed the mag for the rise in salinity....it is part epson salt.

 

[vangogh121]

How are you supplementing alk? It looks like alk burn to me. If your dosing into the sump and your return is pushing it into the corals, it might be burning them before it completely dissolves.


Just a guess though

 

[ludnix]

Salinity is 1.026

I supplement alk with sodium carbonate or BRS supplement. I dissolve the solution in a bottle and slowly add it to my sump. I haven't does recently though.

 

[marmanning]

Did you switch to new lighting/bulb? How about your phosphates?

 

[mod0522]

I had a very similar issue when I upgraded from a 75g to my current 175g. I changed all my bulbs and SLOWLY acclimated all my frags and colonies to their previous distances from the light source. I still had the tips lose flesh just like that on 3 of my pieces. Have you relocated those corals recently?

 

[ludnix]

It is not a lighting issue, any SPS coral is affected regardless of tank or time spent in the tank. All of my corals that didn't die recovered, but I'm seeing it happening again for some reason. It is definitely something related to the water.