Need some help - puzzling sps tissue recession

[Andrew D]

Hi all. I am having some trouble with my well established 350G display, 700G system, and was hoping someone can help. I'll have to do this in stages because my computer's acting up and I need to get the kids ready for school in a bit.

The display has been around since March 2012, but many of the corals transferred from a 150G/300G system that I had for about 6 years prior. System is well stocked, with a wide variety of corals (mostly sps but some lps, mushrooms, zoas, clams, and gorgonians). Picture from a few months back is below...



I've spent a lot of time and money on this tank, and was feeling really proud (yeah, I know) about how far it has come, so this setback is hitting me kind of hard.

ANyway, about a month ago I began to notice rapid tissue loss in some of my sps. I had been struggling with phosphate and nitrate issues for a little while (more on this later) and as I was in the process of bringing these down through GFO and a new ATS I had set up I thought I had identified the cause and didn't contemplate doing anything else. My phosphates have come down significantly though (from 0.5 to about 0.03 at present) and I am still experiencing tissue loss. It has now hit one of my larger and previously stronger coral colonies, which I have had since probably 2008, so I'm thinking it must be something else. I've also had recent trouble with my alkalinity levels, due to a clogged dosing tube which caused it to drop from about 10.8 to under 6 in less than a week. This too has been slowly corrected, with levels brought slowly back up to the current 9.3 ish (all tests with a salifert kit).

More in a few minutes....

 

[Andrew D]

I'm back....

I'm back....

I started to also think that I had a pest of some kind, because the recession looks kind of blotchy in places. I don't a picture but I will try to post later when the tank lights come on. I am admittedly not great at quarantining my corals (I do my fish), but I do dip them and closely inspect before I put them in my system and have caught AEFW in new arrivals in doing so. I took some of the infected corals out and dipped them in revive as many have suggested, but when I looked at the residue I couldn't find any of the buggers nor any eggs on the corals themselves. I also can't find any evidence of red bugs although I am less sure of how these look and have heard that these merely irritate rather than kill.

I think the final pieces to the puzzle are two other changes I have made over the past several months, both well before this happened but nonetheless something that might be contributing. First, after many years using Reef Crystals I began to use H20 because of the better mixed parameters and the very good feedback from others on a local forum. Second, I replaced all of my T5 fixtures and bulbs, from TEK's to ATI power and Sunpower modules. I now have 24 bulbs over my 6*3.5*2.5 display, 18 lengthwise over 4 feet and 6 three footers on the one side. It's a lot of light, but I introduced them gradually and have otherwise noticed a great response from my tank inhabitants including most sps (at least at first).

More later, kids need help waking up...

 

[Andrew D]

I guess I should also add that this seems only to be affecting my smooth skinned acros, and even so inconsistently. By this I mean that my millies, montis, and birdsnests are doing fine, as seem also to be the smooth skinned ones until they start to lose tissue. In fact, i have never seen such good polyp extension as I have recently.

There's probably a lot more than you want to know (and will I'm sure ask) but at this point I'm thinking it's one or more of the following...

1. corals recovering from wide alkalinity swing, which now has stabilized
2. corals recovering from excessive phsophates and nitrates (up near 0.5 and 50 respectively but now at 0.03 and 0 respectively)
3. corals suffering from too rapid a change in the above parameters (although I did take my time with the alk and the ATS took some time to mature as well)
4. a pest of some kind that I cannot find (I have lots of crabs, shrimps, snails, serpent stars in my tank including a few very large emerald crabs that I remove now on sight)
5. corals are getting too much light (can this lead to rapid tissue loss?)

It occurs to me that I never shared my fish load. I have a lot of fish, large and small, but none that are known (to me) as munching on coral and all that are quite well established. I do have 5 wrasse which should also help with any bugs I might have. I can post a full fish list later if you think that relevant.

Anyway, that's all I can think of to tell you. Any help/advice would be much appreciated.

Andrew

 

[nemodan]

Andrew, I will bet that the Alk change was, probably, the main factor. Now you are going back to stability and that is good.

My last comment is,about Phosp/Nitrates and your Alk level. If you are now in 0.03/0 (P/N), I will be thinking to slowly allow the tank to go to an Alk ~7-8 (more to the 7 side). And let the system to acquire again the so needed stability.

Let see if others agree with these 2 comments.

Nice tank !!!!! VERY NICE !!!!

Daniel

 

[ps2cho]

That's a huge drop in po4 without a ratio reduction in alk. Either dirty the water up again or drop the alk closer to 8...

 

[ros_sco]

I had a very similar experience in 2012. My alk dropped suddenly from the mid 9 range to barely 6 in a short time when my CO2 ran out for the CA reactor. A couple weeks later a few colonies started receding at the base, mostly smooth skinned like you. I eventually had to frag over half of my colonies well ahead of the recession to save at least some of them. I am also thinking the sudden alk drop is your main cause.

Keep a close eye on your alk levels now for signs of decreased utilization. Mine swung higher than it had been staying with the same effluent rate after my drop, which made the swing even larger.

One more idea, were you having problems from your nitrate and phosphate numbers or just chasing numbers? Another common theme I see with recession problems is the recent addition of GFO and carbon, one of the reasons I don't use or plan to use either.

 

[tmz]

First guesses are: the alk drop to barely 6dkh ,predation , some detritus buildup or reduced flow areas around the affected specimens perhaps exacerbating night time hypoxia.

I'd probably try to get some interceptor,requires a vet prescription, for a tank treatment but it may kill some pods and shrimp along with predatory micro crustaceans.
AEFW are a possibility but they wouldn't usually restrict themselves to smooth skinned acros.
Reducing PO4 too quickly via removers like GFO could contribute. However, 0.03ppm does not indicate a PO4 deficiency and corals usually pale when one occurs, IME.
The NO3 at zero might be an issue in terms of a nitrogen deficiency but if the algae scrubber is thriving and there are fish in the tank it seems very unlikely even with undetectable readings. Might try a small amount of sodium nitrate to get a sub 1ppm reading ,say 0,2ppnm to 0.5ppm NO3.

GAC can help reduce allelopathic compounds and improve water clairity. I have always used moderate to small amounts.

FWIW, I've run my system for about 6 years with PO4 at 0.02 to 0.04 ppm with occasional variations to 0.01 ppm to 0.05ppm along with NO3 at 0.02 to undetectable . Alk is maintained at 8.5 to 9.5dkh.

Don't know how to asses the light question without PAR data

 

[Ricardo Fonseca]

Alk swings/drop. Had the same problem since August. Alk droped to 2/3, luckely didn't kill all the sps/acros.

Been correcting the levels since, lost about 5 colonies and fragged a dozen more. Some frags died but the majority is ok. Clear up some space in the tank and sold a lot o frags (good health ones).

A lot of water changes from the sea and everything's comming back together in no time.

Just do your thing, keep calm and enjoy your reef.

 

[fearyaks]

I'm by no means an expert.. I'm very new to reefing but I experienced quite a bit of tissue loss when I first introduced my GFO. Some nice colonies disappeared seemingly overnight.

 

[Andrew D]

Thanks everyone for the feedback, and Daniel for the kind words about my tank. I can assure you, things have thinned out considerably since then. Just today I noticed tissue loss on two more corals. Arghhhh!

This first picture is one of my larger colonies, which has shown recession not from the bottom but from the the middle where two branches connect. The branches are quite dense, and before I got the better lights I thought that the inner parts would suffer because they didn't get enough light...



in this picture the mushroom looks close, but it's actually not touching the affected coral.



this one had coloured up so nicely recently...



To respond to some of the comments/questions/suggestions....

Many of you have pointed to the alkalinity swing, and I think you're probably right. I've had fluctuations before, but never so large. If my corals were already stressed because of the drop in phosphates then that could have pushed them over the edge. The comments about alk levels as they relate to phosphates aligns with a thread I read recently, that said that the higher the phosphates the higher the alk and the light intensity should be (or something like that). I'd been keeping alkalinity that high before so I didn't think twice about returning them to that level after the dip. As mentioned though, I did it slowly, over the course of a couple of weeks. The variable though that was different was my phosphate and nitrate levels, which as mentioned were previously quite high. I prefer the ATS to the GFO so I am slowly going to remove the GFO one bag at a time to let levels creep back up. I will also drop my alkalinity back down a tad, to the recommended 7-8, and see what happens.

TMZ, I don't have a par meter but will see if I can borrow one to get a reading. Except perhaps in combination with other factors, I suspect the lighting isn't the problem though. As for interceptor, I don't have any and want to avoid that if at all possible, except of course in some sort of treatment tank. That said, if I find nothing else helps I'll have to take the plunge. I do run GAC, but not in great amounts as I find my water isn't really that yellow when I do the bucket test and also don't have many soft corals which are more noxious. Your comment about detritus build up and hypoxia is a valid one, because although I have a lot of movement in the tank with my 3 vortechs, return pump and closed loop, the coral growth has choked things a bit and I do have what looks like green cyano at the base of some of my corals. YOu'll see this in all of the pictures I've included. I've had this for a while but even though it eventually kills the part of the coral it covers (unless I baste it away quickly) I've not experiencing yet that it kills uncovered parts too. Is this possible/common?

One thing that I didn't detail before but you can see from the first picture, I do have three mini angels including the potters in the first picture. I know they are questionably reef safe, but I've had them for a while and never seen any of them so much as nibble. The only fish I've had a problem with was my cleaner wrasse who took a liking to clam mantle before I caught him and replaced him with another.

Again, I really appreciate your comments, it's nice to see so many willing to offer opinion and help.

Andrew

 

[rovster]

Alk swing is my guess. You obviously have more experience than me (and more success in envious of your tank) but I have made some observations regarding Alk swings. First is there seems to be a latent effect where the damage shows up shortly after but he STN continues despite you stabilizing the parameters. I feel in part it has to run its course. The other thing I've observed in my tank is that after an "event" there can be some aftershocks shortly after, where you think you've fixed it and something unexpectedly goes awry. Hope you figure it out. I'm dealing with something similar myself and part of me is trying real hard to keep my hands it of the tank and not even look at the tank so I'm not tempted to fiddle with it.

 

[71xlch]

Hey Andrew,

Sorry to hear about the tank. I recently had some odd STN, long story short my refractometer was out. Since correcting i have noticed a big difference in just two weeks since moving back to 1.026. Might be worth a check.


Kyle.

 

[nyxx]

I have a much less developed reef than this and I've been experiencing some similar issues. I'm also dealing with low Alk and trying to get it back to being stable. It's always helpful to read through these threads to get some insight. Seems like Alk swings are a common factor.

 

[Andrew D]

Alk swing is my guess. You obviously have more experience than me (and more success in envious of your tank) but I have made some observations regarding Alk swings. First is there seems to be a latent effect where the damage shows up shortly after but he STN continues despite you stabilizing the parameters. I feel in part it has to run its course. The other thing I've observed in my tank is that after an "event" there can be some aftershocks shortly after, where you think you've fixed it and something unexpectedly goes awry. Hope you figure it out. I'm dealing with something similar myself and part of me is trying real hard to keep my hands it of the tank and not even look at the tank so I'm not tempted to fiddle with it.

Thanks, I couldn't agree more. I tend to fiddle around with my tank a lot as well, and it's really hard not to do so now that things are going bad. I've been really busy at work, which contributed to the issue in the first place but gives me a distraction while things hopefully settle down. Question for you, are you cutting out the corals as they recede or leaving them alone in the hopes that they'll turn around? I tried the latter with one of my larger colonies but broke down last week when it didn't look like it was going to stop. I ended up cutting off a fair bit from the damaged base, most of which seems to have stabilized in my in-line 90G frag tank. I did the same to a beautiful large red dragon a couple of months ago, and I think I was able to save a fair bit. Now that I've said that, it'll probably start to recede as well....

 

[Andrew D]

Hey Andrew,

Sorry to hear about the tank. I recently had some odd STN, long story short my refractometer was out. Since correcting i have noticed a big difference in just two weeks since moving back to 1.026. Might be worth a check.


Kyle.

Hey Kyle, funny you shoudl mentioned that. I completely forgot in my original post that I too had some problems with my salt levels. I had been using the plastic swing arm since my refractometer was proving very difficult to read (I have strong glasses). I thought things were OK until I bought another one and it read about .04 less than the other. Yikes, went out and bought a couple more just in case. Luckily, my water wasn't too far off at 1.024.

 

[Andrew D]

I have a much less developed reef than this and I've been experiencing some similar issues. I'm also dealing with low Alk and trying to get it back to being stable. It's always helpful to read through these threads to get some insight. Seems like Alk swings are a common factor.

Agreed, this hobby has a way of reminding people in the most upsetting way how little one knows. There's a wealth of ifnormation in this and other forums, I wish I had more time to read it all.

 

[ajcanale]

Almost identical thing happened in my tank about 6 months ago. Ended up being a combination of low SG (was down to 1.020... Milwalkee digital needs to be zero'd regularly it seems) which seemed to somehow cause low alk/ high calcium (6.5dkh, 470ppm) even though only CA rx has been used, along with some other issues...

Point of the matter... ur SG.. make sure its accurate.

 

[Andrew D]

OK, thought I'd update this thread with my progress (or lack thereof) over the last couple of weeks. At around the time I last posted on the 4th, things had begun to stabilize. My parameters were back within the recommended range, with detectable but low phosphate and nitrates and alkalinity stable at about 7.7, all tested with salifert kits. Additionally, I bought the milwaukee salinity tester (strong recommend this BTW) and my SG is again constant at 1.025. Finally, I borrowed a PAR meter and tested my light intensity which ranged from 500 to 650 just below the surface and 400 to 500 about half way down a 28 inch deep tank. This is the portion of the tank where most of my sps are located, including the affected ones most of which haven't moved in years.

From what I've read and (now) know, these parameters which are maintained through ATO, dosing and weekly water changes should be ideal. Unfortunately, even though things stabilized for about a week I have once again begun to lose corals. Over the last few days I have had to frag and discard about 5 big colonies, all of which I have had for 2+ years. My birdsnest is also now affected and one of my millies is starting to lighten up significantly. I don't know what is going on but it's becoming really discouraging. I know this is rash, but I'm tempted to remove all of my sps because I'd rather get it over with than watch them die one by one. Yesterday I pulled a large maricultured purple bonsai...





After dipping and on inspection I still coudln't find any pests or eggs, nor do I really see the bite marks that usually characterize things like AEFW.

One thing I noticed which I'm not sure matters is that the thermometer that I had in my overflow box had broken, and whatever was in the bottom had leaked out.



Could this have contaminated the water sufficiently to do this kind of damage? I don't think so because in that same overflow are small little snails who I thought woudl be much more sensitive to any such pollution, but I mention it just in case it might be relevant. At this point, I'm looking for anything that might explain what is happening.

ANy help/perspective would be very much appreciated. Thanks, Andrew

 

[vinhle00]

the mercury in that thermometer could've leaked into the water. Maybe run some carbon if you haven't yet.

Sometimes when you fix whatever causes the rtn/stn it'll still run its course. Hard to stop it once it starts.

Sorry for your loss and good luck.

 

[Icefire]

The alcohol look intact, only steel balls must have leaked
You can run polyfilter pad to be safe
Did you double check your Alk test kit?