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asylumdown
02/21/2014, 12:45 AM
Hi folks

I'll try and be brief as brief in this explanation as I can. I'm nearly at my wits end.

my tank is now 2 years old. SPS dominated 275 gallon reef (375 gallon total water volume). Tank is lit by 8 gen 1 radions, skimmed by a Deltec SC2560 internal skimmer, with nutrients managed via GFO and a reef dynamics recirculating biopellet reactor. Params are maintained by an auto doser running a 3 part (calcium chloride, baking soda, and Seachem magnesium) dosing program.

I've had outstanding success over the past year and a half, with limited algae growth, and SPS growth that's consistently impressed me. the majority of my colonies are the size of dinner plates, even though I bought them from frags.

About 3 weeks ago, I started having trouble which appeared in the form of burnt tips on a few colonies. I'm now at the point where 50% of my corals have visible damage, with 2 or 3 dinner plate sized corals on the verge of total collapse, and zero visible growth on all colonies. Unfortunately, a few things have changed in my tank recently, and I'm having a hard time pin-pointing what the issue is. Here's the recent history:

leading up to the holidays, I was battling a cyano issue. I credited this with a) cyano being resilient as heck, and b), my tank bioload having reached 'heavy' requiring lots of feedings. To combat it, in... I want to say november (might have been December), I dosed my tank with chemiclean. That knocked the cyano right out, but to make sure it didn't come back, I started an aggressive campaign of dosing with MB7. This triggered a bacterial bloom in my BP reactor the likes of which I had never seen, and, being a recirculating model with an obnoxiously small effluent line, very rapidly lead to my BP reactor clogging up. About a month ago, when I was so busy with school I barely had time to change a filter sock, I failed to check on my reactor for 5 days. In that time, the effluent line clogged up with such a thick bacterial biofilm that all water transit through the reactor stopped. Even though the pellets were still tumbling (it is a recirculating reactor after all), no oxygen was entering the reaction chamber.

The night I opened it up to check on it, my roommate, who was asleep on another floor with the door closed, came running downstairs in a panic thinking there was a gas leak. I've never experienced a smell like that before, and I hope to never experience it again.

No water from the dead reactor made it back in to the system, however, and I completely cleaned it out. I then modified the effluent line so that it couldn't possibly clog up again (this involved a drill press and some 1" pvc piping), and set it back up. The reactor is now churning away, producing a huge amount of bacterial mulm, which goes straight to the skimmer. I'd say that it is working efficiently for the first time since I set the tank up. This is backed up by the fact that since I 'fixed' it, the light dusting of dinos that has waxed and waned on my sand bed (I've confirmed their identity via a microscope) for the past 18 months has vanished completely, and I now need to clean my glass every 5-6 days instead of every 2.

Since Christmas, the other major changes have been: I ran out of GFO and switched brands to a high capacity bulk version. I've run GFO from day one, and have changed it every couple of weeks to every month depending on my maintenance schedule, but the brand change was recent. I have also periodically run carbon in the past, but always Kent brand, and not in a while. At the same time I got the GFO, I got a bulk order of ROX carbon and put some in a bag in my filter sock. I also switched from H2Ocean salt to Seachem's reef salt. The final change was that I switched from the 'oh-my-lord-you-cost-how-much?!?' brand of Seachem anhydrous calcium chloride, which lasted me 2 weeks per bottle, to a no-name (but from a very well respected distributor in Canada) brand of non-anhydrous bulk calcium chloride. This required some adjustments to my dosing regime, but I managed the switch using my test kits to make sure the dosing amount was correct.

So, that was a novel - but the result of all of that is that I now have a tank full of dying corals. As of today, my levels are:

calcium - 360ppm (low)
dKH - 9.0 (very high compared to where I normally keep it, which is 7)
mag - 1300.
nitrate - 0 (but I've never tested anything but zero)
phos - 0 (but I've never tested anything but zero)

The major damage to the corals has all been in the last 3 weeks. The changes in the last three weeks were the ROX carbon, the new brand of GFO, and the 'fixed' biopellet reactor. The changes that preceded the coral damage were the salt brand change, and change of calcium supplement brand. I keep cutting back my dosing rate of alk every time I test, but the levels keep climbing. I think it's because my coral growth rate has plummeted, so even with DRASTICALLY reduced dosing rates, the levels are still going up. I think the increase in alk has suppressed my calcium levels.

So - here's my three main hypothesis, and I'm hoping for some feedback:

1. My nutrients, which were never high enough to show up on a test to begin with, plummeted when I fixed my BP reactor. This caused coral growth rates to slow down, which caused my alk to spike, which caused burning and damage, which in turn lead to even higher alk levels because of the auto-doser. But is an alk of 9 even high enough to cause burning in an ULNS?

2. Something in my new brand of GFO or carbon is damaging my corals, which is causing my alk to spike.

3. Switching salts, which took a few water changes in such a large system to play out, is causing this issue.

Basically I'm not sure what to do here. I've got colonies I couldn't remove without a chisel and a bucket turning in to skeletons before my eyes. I thought maybe it was a 'shock' period that would pass, but every day something else is getting damaged. I'm terrified to start messing around with too many things and making it worse. Essentially I'm looking for 'sage advice' to guide me on what I should take offline/modify first.

tmz
02/21/2014, 01:05 AM
I use rox and HC gfo and have for years without issues,fwiw. On the other hand there was a contaminated bucn of Kent ref carbon that killed of a number of tanks a year ago or so due t ohevy metal poisoning.

UNLS whatever that actually means, presumably as little PO4 and NO3 as you can manage or zeros without all of the supplements associated with those systems can be problematic . I'd suspect your #2 scenario. I'd drop the gfo and slow down the reactor or back off the pellets and bacterial supplement . Let a bit of phoshate and nitrate to build up. I have good long term (5 plus year results ) with NO3 at arounf 0.2 and PO4 in the .02ppm to .04/5 range as tested with a hanah 713 colorimeter(which has a pretty typical +/- 0.04ppm accuracy rating). Alk is around 9.5 dkh with alcim around 450 ppm . I don't use pellets but prefer vodka and vinegar .

Looks like you made 4 major changes that could have severely dropped PO4 and dissoved nitrogen levels
and one that could have added excess organic C and sugars ;ie, stronger gfo, more bacterial activity from the turbo charged reactor, stronger gac, and a large water change.

I assume you know the odor was sewer gas( hydrogen sulfide) which is toxic.

asylumdown
02/21/2014, 01:13 AM
I use rox and HC gfo and have for years without isues,fwiw.

UNLS without aal of the supplements associated with those systems can be problematic . I'd suspect your #2 scenario. I'd drop the gfo and slow down the reactor or back off the pellets and bacterial supplement . Let a bit of phosaphte a nitrate to build up. I have good long term (5 plus year results ) with NO3 at arounf 0.2 and PO4 in teh .02ppm to .04/5 range as tested with a hanah 713 colorimeter. I don't use pellets but prefer vodka and vnegar .

I assume you know the odor was sewer gas( hydrogen sulfide) which is toxic.

Oh yes, which is why I didn't let a drop of that water get back in to the system. I literally shiver thinking about what would have happened had the blockage suddenly cleared itself and nearly 2 gallons of putrid water re-entered my system. This will be my one and only time using a recirculating reactor design. Even with a large effluent hose, the rate at which water leaves the reactor is just not fast enough to deal with bio-films. I've had to clean my 'modified', 1" effluent pipe of a thick slime already.

OK, I'm going to take the GFO reactor offline. I'll also throttle the flow through rate on my BP reactor.

I've gone from dosing 165 ml of alk solution/day to 115 ml of alk solution a day, and my dKH is still 9. My corals are not taking anything up at all.

IanWR
02/21/2014, 08:54 AM
I think what has damaged your corals is rapidly swinging alk, combined with a rapid drop in available nutrients. Fixing your BP reactor, and switching brands of GAC and GFO all in a short time (along with minor changes made with switching salt,etc) shocked your corals, which changed their growth,which exacerbated the levels, which really shocked the corals, ....

Rather than taking anything offline, I would reduce the amounts of each. Take out some pellets, some GFO, and some GAC. Also a huge water change or 2 to help reset everything. If anything, after your big water change take your dosing offline and test daily to see what you actually need to dose.

Sorry to hear about your continued headaches!

- Ian

afishionado
02/21/2014, 09:31 AM
You need to drop your Alkalinity, slowly, down to preferably < or = 7-8dKH ...

Burnt Tip Syndrome, if this is indeed what your Acropora are exhibiting (no pictures provided), is predominantly caused by high dKH levels in low nutrient , often carbon dosed, systems ... There are other factors involved as well, most of them contributing to the above phenomena, but the important/crucial aspect is to lower your elevated dKH level, immediately !

I would recommend simply not dosing as much supplement, 1/2 to 2/3 of whatever systematic option you've implemented, thus allowing the Alkalinity value to slowly decrease "naturally" and without haste ... Given your current conditions/symptoms, it's important not to stress the specimens further. Make changes , slowly

asylumdown
02/23/2014, 05:37 PM
Hey does anyone know the ratio of carbonate to borate present in Fluval Sea Salt?

I've only been able to get my dKH to fall 0.06 in 3 days with more than halving my dosing rate, confirmed with both a red sea alkalinity test, and a Hanna checker. Coral damage continues unabated :(

I just checked my phosphate levels, 0.06ppm as per measured on the Hanna ULR checker, and my nitrate test kit still shows undetectable, but it always has.

I'm not sure if I should do a few large water changes at this point, I haven't because I don't have access to a salt that mixes up to less than 9 dKH.

asylumdown
02/23/2014, 10:15 PM
alright here's some pics. I haven't bothered to try and correct the white balance on the iPhone pics (stupid LEDs), but you get the point:

This one is losing tissue where the corallites join the main stalk. All that brown you see is the light dusting of dinos that have colonized the freshly bare skeleton
http://i1100.photobucket.com/albums/g411/asylumdown/IMG_6496_zps69bc2dfa.jpg (http://s1100.photobucket.com/user/asylumdown/media/IMG_6496_zps69bc2dfa.jpg.html)

This guy lost tissue at the tips right where the light was brightest, all of a sudden, across the whole coral, practically over night
http://i1100.photobucket.com/albums/g411/asylumdown/IMG_6497_2_zps94a5451f.jpg (http://s1100.photobucket.com/user/asylumdown/media/IMG_6497_2_zps94a5451f.jpg.html)
http://i1100.photobucket.com/albums/g411/asylumdown/IMG_6498_2_zps35267a05.jpg (http://s1100.photobucket.com/user/asylumdown/media/IMG_6498_2_zps35267a05.jpg.html)

This has been a slow loss of tissue at the tips, steadily getting worse
http://i1100.photobucket.com/albums/g411/asylumdown/IMG_6500_2_zpsb9bb43a6.jpg (http://s1100.photobucket.com/user/asylumdown/media/IMG_6500_2_zpsb9bb43a6.jpg.html)

This guy looks like its been almost shucked
http://i1100.photobucket.com/albums/g411/asylumdown/IMG_6501_2_zpsfb3d8302.jpg (http://s1100.photobucket.com/user/asylumdown/media/IMG_6501_2_zpsfb3d8302.jpg.html)

And this is my hardest hit coral. Unfortunately it's also one of my oldest. I grew it from a frag, now most of it is a dinner plate sized skeleton
http://i1100.photobucket.com/albums/g411/asylumdown/IMG_6503_2_zps0570125c.jpg (http://s1100.photobucket.com/user/asylumdown/media/IMG_6503_2_zps0570125c.jpg.html)

And finally, the corals that haven't lost tissue yet are doing this weird swelling thing, you can see on this one it looks like little tiny bubbles have formed on the corallites. I'm not sure if this is stage 1 of losing tissue everywhere. Also this coral used to be blood red.
http://i1100.photobucket.com/albums/g411/asylumdown/IMG_6504_2_zps805f67ad.jpg (http://s1100.photobucket.com/user/asylumdown/media/IMG_6504_2_zps805f67ad.jpg.html)

I did a major water change tonight with the salt I've used for the past 2 years, not the fluval sea salt. I'm not blaming the fluval salt, but it's one more variable that's changed that I can't account for. Tested my params after the change - alk 8.5, calcium 375. I picked up some Tropic marin Alca-Balance today and just dosed a bit to hopefully bring my alk down a little further, I'm aiming for 7.5. I'm REALLY hoping this works.

tmz
02/24/2014, 12:22 AM
I hope dropping the alk helps. It may have gone up as the corals slowed down their consumption for some reason.. I don't claim to know what causes burnt tips; could be a number of things independently or in combination : nitrogen deficincy, too little
PO4 , excess glucose, hypoxia, a missing element like iron or K and so on.I'm sorry to see the trouble you are having. I think the extra PO4 youhave now will not hurt and may help. A source of nitrogen might help too;ie. a little extra food,ammino acid or maybe even some sodium nitrate.NSW nitrate runs around 0.2ppm near the sruface of reefs.

SoLiD
02/24/2014, 05:54 AM
Wow, you have some nice SPS colonies. I hope you get it fixed. Do you run a bare bottom or deep sand bed?

MondoBongo
02/24/2014, 10:12 AM
this is a total hail mary, as you are well past my skill or knowledge in this hobby, but have you checked in your sump and around your plumbing for any metal?

a rusty hose clamp? a coin or something else that accidentally fell in to the sump?

i've had a few hose clamps that were way away from the water go rusty on me and start leaking rust water in to my sump before, and i've heard stories of people finding pennies or other metal objects that somehow accidentally fell in to their sumps.

again, it's a long shot, but could be worth a sanity check. i hope you get this figured out, you have a gorgeous tank.

trinidiver
02/25/2014, 10:24 AM
this is a total hail mary, as you are well past my skill or knowledge in this hobby, but have you checked in your sump and around your plumbing for any metal?

a rusty hose clamp? a coin or something else that accidentally fell in to the sump?

i've had a few hose clamps that were way away from the water go rusty on me and start leaking rust water in to my sump before, and i've heard stories of people finding pennies or other metal objects that somehow accidentally fell in to their sumps.

again, it's a long shot, but could be worth a sanity check. i hope you get this figured out, you have a gorgeous tank.

I new there was something I forgot to do before I left the country? I have one rusting in my sump.

asylumdown
02/25/2014, 05:58 PM
Did a thorough check, no metal in the sump or tank anywhere. This morning one of my favourite colonies had huge flaps of tissue hanging off it's skeleton flapping about in the current. I can barely even bring myself to look at my tank anymore.

ca1ore
03/05/2014, 08:08 AM
Fluctuations in alkalinity are more problematic than absolute levels, and can cause burned tips. I run at a dKh of 10, with low nutrients, and have no problems, but the levels are rock solid.

When my tanks looked bad, for whatever reason, I always ran a polyfilter for a while - in fact, on my current tank, I run them 24/7. You could try that. Also, doing a big water change is always a good idea.

Have you noticed any changes in the production from your protein skimmer - particularly an excess of foam?