Some Acros Dying Slowly

Overboard · Dec 27, 2019

Hey! I could use some help.

Generally, my tank is doing pretty well. Parameters are stable, low levels of PO4 and NO3 ( but not 0) good lighting and the system has been set up for a couple of years. Alk at 8.4 and Calcium at 425-450. Most acros look good with polyp extension at night. About three months ago, it seems like I have slowly lost one coral every 3-4 weeks. It is not RTN or STN but the edge of the coral seems to apparently die and just get calcified. This slowly progresses until the entire coral is gone. I would appreciate any ideas. Thanks!

C. Eymann · Dec 27, 2019

When you say polyp extension are you saying overall? because the tips of the branches (axial polyp) is the best indicator of happiness when it comes to PE at night.

Good pics of the colonies, before, during and after tissue recession is highly valuable to getting a correct diagnosis IMO

Overboard · Dec 27, 2019

Here is a good example of one that is having the problem right now. You can see there is some minimal PE on this one in the green areas. On the healthy corals, both axial and radial corallites show PE. Obviously, something up though. Just stumped. I have not had problems with pests in the past and no new corals have been added in many months. Most of my frags came from very experienced friends in the hobby with stunning tanks. I quarantine, but really for ich and velvet. Dip has been Revive.

Overboard · Dec 27, 2019

No idea why it posted the pic sideways!

ycnibrc · Dec 27, 2019

How old is your tank? 9mon to a year? Start from dry rock or live rock?

Michael Gray · Dec 27, 2019

ycnibrc said:
How old is your tank? 9mon to a year? Start from dry rock or live rock?

I hate this answer (dry rock) as I started from dry rock and all sps turn white in my tank. But my tank is almost 6 months. I hate the idea of waiting 2 years to be able to grow a acro. If I knew this I wouldnt have done the dry rock route.

bums me out!

Overboard · Dec 27, 2019

The tank is over 2 years old.

flyfisherman · Dec 28, 2019

which corals are thriving if any? which have died?

Overboard · Dec 28, 2019

Seems random. Some Millis, Torts, Tenuis seem good, others don’t.

Thinking flow might be part of the issue. I have two large Gyres (280), a single WAV, and a single Tunze, along with the return from the sump. Seems that most of the corals affected were mid level in the tank so I am going to add a Eco MP 40 at that level.

flyfisherman · Dec 28, 2019

have you checked for metals or other elements that may be off? do the triton test. could be a magnet or something else poisoning them. they usually wont all die right away...

Overboard · Dec 28, 2019

Have not thought about testing for metals. Good idea!

SeaDweller · Dec 28, 2019

what about your source water, how clean is it?

Overboard · Dec 28, 2019

Good thought.

Our water at the tap has very high TDS, around 200. I use an RO/DI with double carbon blocks (we have chloramines), DI , etc., so the TDS is 0 going to my storage tank. Just checked it again to be sure. The filters are fresh...now. I may have waited a little long on replacing the filters this last time so that could have been part of the problem. Test strips always showed zero for Chlorine (and I needed to change the battery in the TDS meter) but I have read they may not be that dependable. Ordering the Hanna checker this weekend.

flyfisherman · Dec 28, 2019

Overboard said:
Have not thought about testing for metals. Good idea!

cross your fingers its a corroding magnet otherwise its probably young tank syndrome. i would slow down water changes if the triton test indicates perfect water. i dont think sps like too much water exchange.

motortrendz · Dec 28, 2019

Overboard said:
Good thought.

Our water at the tap has very high TDS, around 200. I use an RO/DI with double carbon blocks (we have chloramines), DI , etc., so the TDS is 0 going to my storage tank. Just checked it again to be sure. The filters are fresh...now. I may have waited a little long on replacing the filters this last time so that could have been part of the problem. Test strips always showed zero for Chlorine (and I needed to change the battery in the TDS meter) but I have read they may not be that dependable. Ordering the Hanna checker this weekend.

Remeber chlorine and chloramine are 2 different things. Chloramine is a derivative of amonia.