Just lost half my colonies to RTN. What Gives?

bassking16

Member
Ok, I've never been so dissapointed in this hoby as I am right now. My tank has been up and running for almost two years with no problems, and now all of a sudden I'm lossing colonies left and right all of wich are at least a year old or more. The RTN started between two corals that I thought were touching thus killed eachother, but has spread outward from there. So far, I have lost 9 acro colonies and one large green birdsnest in about three days. I have tried everything, and I am at a loss. Please....any suggestions are welcome.

I run a 150g SPS dominated reef. Nothing has changed in the last six months other then the addition of my Foxface Rabitfish about a month ago. I do bi-weekly water changes, and my bulbs are not that old. My T5's are about 9 months old, and my 250w 14k Phoenix bulbs are less then 4 months old. LPS corals and fish all seem fine.

Parameters:

SG - 1.024 steady
Temp - 79-82
Alk - 8-9 (API)
Nitrate - Undetectible (Salifert)
Phosphate - Undetectible (Salifert)
Nitrite - 0 (API)
PH - 7.9-8.1 (Recently calibrated meter)

I tried dipping a couple corals that were RTNing, and no pests came off. No AEFW or Redbugs.

I have to be missing something here, but I am at a loss. If anyone can help me out, I would be extremely appreciative. Thank You.
 
I forgot to mention that I have a little bit Xenia coral as well, and it has started to wilt, and not look so happy over the last few days as well.
 
Verify your SG. Something has swung. If it makes u feel any better I just lost a colony after a year and a half. All it took was a Aussie Elegance to go a little bit crappy and BOOM, colony gone! :eek1:
 
Is the rtn starting at the base or the tips?
What do you store your top off water in?
Try to borrow a hanna to check phosphate, salfert will not get low enough.
What do you check SG with and have you calibated with pinpoint solution?
 
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Verify your SG. Something has swung.

+1 something is likely off...I would double check every parameter..I had a very similar situation a few years ago and it was my alkalinity test that was off...had gone through the roof until I realized it.
 
The rtn is a little wierd actually. Like I said, I thought it was corals that were touching, and killing eachother. On most of my dead colonies, the rtn started at one side and worked its way accross the coral. However, my prized hawkins is rtn'ing starting from the base and working upward. This was also the case with my Miami Orchid. My red planet is starting at one side of the table, and going accross starting from the direction of the first two colonies that died, as is the same with another table acro that is about half dead right now.

I store my topoff water in a glass tank which gravity feeds my sump. This has been my setup from original design two years ago.

Unfortunately I don't know anyone with a hanna checker, however, both salifert and api read 0.

I just recalibrated my refractometer this past weekend when everything started to die. it was still on the money, and my tank is reading at 1.024.

I'll get a new alk and calcium test kit tomorrow, and try it. My alk is reading between 8 and 9 on both api and red sea testers though.


Has anyone ever seen two corals kill eachother from touching, then spreading the rtn to surrounding corals? That is what seems to be hapening. I even fraged a few good pieces from the affected corals, and placed them in my seperate frag tank, and still they RTN'ed over night. My frag tank has had frags in it for over six months now with no issues, and any frags that were already in the tank prior to all this are still fine. My frag tank params are almost exactly the same as my display tank. The temp is about a degree warmer, but otherwise the same.
 
Just a shot in the dark, but how about your water temp? You didn't mention that with all your other parameters. I thought of it when you mentioned your Xenia Looked wilted. With summer here maybe the temp fluctuated too high?
 
How is your flow? Seems to me RTN starts from one (the same) side on most of your corals,maybe there is not enough flow coming from this side.Remember as your corals grow bigger, what used to be good flow might not be the case anymore.If all your parameters check out ok ,I would try to increase water movement from the side you're getting RTN.Just another shot in the dark.
 
gosh... i hate to hear about stuff like this... as you probably already know, welcome to the world of sps keeping... there is so many factors and things to worry about and keep constant and stay on top of...... sometimes you jus dont know whats going on and you find yourself beating your head against the wall... i am kinda new to the sps world and already know this :(

GL friend, i hope the best for you and that it works out... though if it doesnt, please dont give up and push forward...
 
Have you checked for any current/voltage leaks in your system? Couple of years of running could definitely cause enough wear on pumps to start leaking.....everything else seems to be ok
 
And i do believe it is possible for coral warfare to spread throughout the tank but that seems very odd to kill all the sps so quick. there are guys with huge reefs and corals touching all the time and not causing any major damage so its kindof an iffy say whether that was the cause or not
 
I hope this is not the case but check for pest like Aefw . Take out one of the coral and dip them and see what comes off of them. Ok never mind just read the last of your post were you diped already. Yeah might be alk
 
Hey bud, sorry to hear about this. I'd say as long as your doing some extensive testing you may as well test for copper. You never know. Not sure if you have kids, but stranger things have happened than something like a penny or a small strand of wire or something along these lines finding there way into your tank. At least rule it out.

Is the frag tank connected to the DT?
 
My frag tank is a seperate system all together. I did check for stray voltage this morning, and unfortunately that is not the problem. Thanks for mentioning that though. I didn't think of that.

I do have a couple kiddos running around, and it wouldn't surprise me if something foriegn was introduced to the tank. It will take a little bit to get a test kit though. I don't have a copper test currently, so I would have to order one.

I did notice this morninng that my water temp was about 1 degree warmer then normal for that time of day. Typically my tanks stays at 78 degrees at night, and climbs to between 80 and 81 during the day. We have had some extremely hot weather here in Texas lately, so maybe this is what happened. I use three 4xFan units to cool my tank timed to come on with my T5's. I went ahead and put the fans on full time this morning, so we'll see if that helps.

My lights weren't on when I left for work, but under the LED moonlights, I could see that it looks like the RTN might be slowing down a bit. My red planet and green birdsnest seem to be hanging in there. However, my Hawkins, and blue tip green table are completely dead now.

If I can't figure this out soon, I will have no choice but to let it run its course, and then start over with what's left. I want to do a 40 to 50% water change, but I'm affraid of stressing the corals even more by being exposed to the air.

Incidently, I did notice one other consistancy with my issue. All the corals that are suffering, are near the top of my tank, and the RTN started almost in the center. I have a few sps in the lower half of my tank, and they seem to be doing fine. Good color, and polyp extension as usual. Not sure if that means anything.

Thank you all for the suggestions. If you think of anything else, please post. I am still pretty much at loss. Maybe the temp did it, but I'm hesitant to say that ssince it has been higher then that in the past with no issue.
 
Have you checked all hardware? Could be a long shot but I had a Vortech wet side leach junk in my tank over the course of many, many months. It even transferred to the new tank as I was unaware what was happening up inside the pump. I changed out every bit of hardware including a new tank...except the Vortech wet sides when I set up my new reef. It took 4-5 months before the pump failed in the new tank and I found the problem. I would look closely at all pumps, take them apart, check your heater/s, anything that could be leaching something in the tank. Once I figured out what had happened it made sense why my first beautiful reef crashed with unexplained RTN/STN over 8 months, then why my new reef was doing the exact same thing. I had to remove all rock and sand and start over for the third time. Once all the rock and sand were removed the tank began thriving. I spent months testing params, doing water changes, changing salts etc. Never knowing that the pump was the cause. It was awful. Things are much better now :D.
 
I don't have any more ideas for troubleshooting, the ones mentioned seemed great. I still would try a different method of checking your specific gravity, perhaps with a different meter. I have had stray voltages nearly wipe out a tank before. Could there be any equipment that wasn't actually on when you tested for voltage in the tank?

As far as the corals go, I hope the STN will stop on its own soon. In the mean time, something I have always done when a coral starts to STN is cut the dead portions off. This probably won't help much, as it seems your problem is in the water column, but it may be worth a shot. Additionally, CoralRx claims to be able to stop coral STN'ing. I'll keep my fingers crossed for you.

Nate
 
As an after thought, posting pictures of your corals may help...? And if you haven't put carbon in there yet, I'd get a bag in asap.
 
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