selective disaster to sps---via alkalinity.

Sk8r

Staff member
RC Mod
Several things happened recently...or how to really screw up.
1. I got the flu and was semiconscious for a couple of weeks, just after being out of the house for 11 days, just after new years, just after Christmas...can you say major tank neglect?
2. My system over-buffered and drove alkalinity up to 12 dkh. It should have been 7.8 to 8.3.
3. I did a big burst of tank maintenance, and replaced the 10000k Ushio 250 with a Reeflux 12000k 250, but did burn it in carefully.
4. I got a new skimmer, replacing an Urchin with the Aqua C EV120. MUCH stronger skimming or I'd be in worse trouble than I am.
5. I decided to remedy the high alk by benign neglect, and just let topoff handle it. I think this was a mistake...because a little RTN turned into big RTN.

Here are the odd particulars: I lost monti cap, but digitata survived; LPS is fine, except the candycane isn't happy; frog and hammer are great; lost pocillopora; stylophora; and all acroporas---EXCEPT the thriving aculeus colony, which I am told demands light, and is sensitive. It's perfect. THe valida is hanging on but not happy.

So how does this add up? The 12000k Reeflux should be easier on the sensitive corals than the 10000k Ushio, but here I am with major troubles. I went for a consult with my lfs, thinking maybe I should change bulbs back to the 10000k. My lfs guy is a reefer, old time, frag-growing reefer, and his assessment, after studying the whole situation, was that the problem was the alkalinity, which has slowly gotten back to 8.3. That ocean alk is around 7.8-7.9, and 12 was a real problem. The lights are innocent; the skimmer has only been helping.

So I'm back to water tests and trying to get stable. The nasty thing is this is right before I have to move the tank. So we'll have another round of instability. I'm not going to replace any sps until after we're in the new place.

I offer this as a case study in RTN sneakiness. That alk just crept up on me, in a moment of inattention, and here we are. I don't blame anybody but myself. But if you're running high alk, knock it down at bit, and I think you'll have less trouble with the sps.

Discussion and observations welcome.
 
i would have to diasgree about the Alk being 12 a problem. Alk at 12 should be ok IMO. Maybe the multiple changes done to your tank in such a short span had something to do with it??
 
That's what I had thought. And I have often heard on RC that an alk of 12 is ok, which is why I thought I might write my own experience with it. So long as I was at 8.3, things grew and thrived. There WERE certainly a lot of changes, and that certainly is highly suspect. But the aculeus is a peculiar case. It's, according to my source, quite sensitive to burning, yet it didn't when the light was changed. Everything else suffered. It's also the only sps that's actually gone colony, and that could be relevant. Yet my source keeps his tanks and frag tanks at 8.3, and hearing all that had gone on, and being able to sell me a new bulb if that might be the problem, he talked me out of a change back and is maintaining that the real heart of the problem is the rise in alk. He said he's had a number of friends in the trade that have had mysterious RTN when the alk gets up, and he personally keeps it lower. So I'm going to gamble on that solution, rather than a change back of the light, at least---in the theory that if too many changes are potentially a problem, more changes aren't going to help.

Ah! One other datum: I had also had very high phosphate, which the new skimmer is helping export, hand over fist.

Could it be bi-causal? Ie, not just the high alk, but the high alk combined with high phosphate?...the way they theorize that bleaching is not just high heat, but high heat combined with strong light? A dual cause could make it ghosty, indeed.

I appreciate your input. That's why I posted my whole messed up situation. I think there's some worthwhile possibility for discussion on this tank, and I'm still absorbing opinions and info. All opinions valued.
 
Yes 12 wont necessarly kill your sps, IF IF IF your corals are used to that level. However, if your corals are used to 8.0 and you bump it to 12 in a short time, that WILL cause TN no doubt about it. SPS dont like shifts in Kh. Kh problems IMO are the #1 killer of SPS. SPS are actually much more hardy than many like to admit, but if you dont keep your Kh stable your going to have problems, plain and simple. I have had multiple Alk spikes (accidental overdoses of KH), and just having the tank at a high level for a matter of hours burned the tips on some of my corals. It happens almost instantly after the accident and takes a few weeks to heal. If I was to not take corrective action I probably would have lost everything as well.

I would also like to say this one thing. For those of you using buffer STOP!!!!!! When you add buffer, it makes your Kh skyrocket. Trying to control your PH with Buffer is a losing battle and your playing russian rulette with your SPS. PH is nothing to really worry about unless it is WAY off. Your tanks PH is going to settle whereever its going to settle and there is little than you can do about it. Pretty much the ONLY thing you can do is ensure you have proper ventilation to your tank. IF your house has excess Co2, that is what will cause low PH. The only way your going to solve this is by getting fresh air into your tank. Some people put thier skimmer airline out a window for fresh air.

HTH
 
ive had alk up past 20 on one occasion and there were no losses and not much damage, a bit of burnt tips on a few acros, but that was it.
 
How was your phosphate during that alk spike, twon8? Was it low? I'm really curious about the combination of problems aspect of this.
 
I had mine spike to around 15 mEq/L and mine decalcified at the tips and began a slow encroaching necrosis. I think a combination of things are what you experienced, not necessarily one thing in particular. What you experienced doesn't really add up to one particular thing, IME. Horace, what do you mean by not adding a buffer? Are you speaking generally, as in some proprietary buffers or are you referring to actual buffers (NaHCO3 is a buffer in itself)?
 
Yes, I'm interested in this too. I have a smallish tank, a 52 g, so some equipment is overkill for me, but can you elaborate on maintaining alk without buffer? Are we talking Kalk? I've been using Kent dkh buffer and Kent Turbo Calcium, and was doing great...until...

I'm naturally bummed out about this event, but it's interesting what it's turned up, informationally. I think there's a lot for me to learn here.
 
Ok let me be more specific... Some people add "buffer" to the tank specifically to maintain a given level of PH in the tank. I dont typically speak of a Dkh dosing product as "buffer". For example, seachem sells both Reef Builder and Reef Buffer. Reef Builder is a carbonate alkalinity supplement, where Reef Buffer is supposed to maintain a PH level of 8.3 AND maintain Alk. The problem is people using this product forget its effect on the DKH and focus on the PH. So while trying to maintian their PH, they screw up thier Alk levels which are MUCH more detrimental to coral health. If I misunderstood what you were using the buffer for them Im sorry. It just seemed that you may have made the same mistake, which is why your alk was up over 12dkh.
 
Horace, thank you. What happened was an overdose of Kent dkh buffer in my topoff, which happened because I was in a hurry, as best I can figure, and went on to when I was sick and not monitoring levels [failure to test, in other words: my bad]. I've never understood kalk, but by what I read in the chemistry forum, I could just put kalk [instead of buffer] in the topoff reservoir at 2 tsps per gallon [I have a 5g reservoir] and it would never go beyond saturation level. Plus it would also handle the calcium requirement, but never have the over-accumulation of buffering that built up while I was making micro-mistakes with the Kent buffer---because it only goes to saturation, and no further, keeping all excess as 'mud' in the bottom . Am I reading this right, or am I confused? One of my problems is a little bit what nanos run into: micromistakes in a 52g over a year's time add up. I do my water changes, but hadn't during that period; and what I wasn't accounting for is evidently what built up in the topoff reservoir---one overdose [and failure to test] atop that situation did me in.

All of which is to ask some wiser heads---would I be smarter to change to kalk in the topoff? And would 2 tsp per gallon be the right dose?
 
I don't think it is the alk either. 12 is not a bad number. Many, many people keep their alk at 14 on a regular basis with no problems.

Changing both the skimmer and the bulbs at the same time is not the best idea. just one can dramitcally change your reef, both at the same time can cause real problems if you don't pay attention. then you have a while of reef neglect which doesn't help much either.

Amazing how fast things can take a turn isn't it?
 
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Everyone is being very kind. Stupid mistake on my part, I'll say it---when I wrote that bit about 'a sudden burst of tank maintenance', a little alarm bell went off in my head, and you're very right. I got off without a crash, and I'm glad of that. One thing you can say: a 52g is right on the lower borderland of big-tank stability: I just have to be more careful and go back to daily testing for a while. But I am still interested in this kalk thing, which looks as if it has bennies of ease of operation, with a natural up/down cycle that drives corals to consume more if the chemistry wobbles, hence self-correcting, within limits. Again, the fact I am a 52 gives me a little pause, because of that lack of big-tank stability: changes for me happen faster, and what would be a micro-swing for a big tank can get out of hand fast, too.
 
Over the weekend, I just have a colony 5x5" of SPS RTN in 2 days.

i have 4 other Colony in the tank and all of them are fine. I am struggling to find a answer to this mysterious RTN and it interesting that I read from your episode because the only change I had before the disaster is that i change the 1/4" tube of my Calcium reactor that cause my drip to be a little faster and increase my Alk to around 12dkh and calcium to 470. I checked other parameters and they are fine.

I really doubt that 12dkh is a problem but seem that is the only explaination that I can come up with.
 
as others have stated before, i dont think 12 dkh is an issue if it is a stable level. i run my alkalinity around there all the time. i think problems arise when there is change over a short period of time. for example, my calc. reactor media was about spent and i ran out of CO2 all in the same week. because of that, i went without the reactor for three days, and forgot to dial down the kalk reactor, so my alkalinity dropped a bit. when i put new media in the reactor and turned it back on, my alkalinity rose too fast, and a few of the acros in the tank receeded at the tips (these were all closest to the return lines carrying the water from the sump that would have higher alkalinity than the tank while it was rising). now that things have levelled back off, the tips have covered back over and things look fine again.
 
I'm taking very seriously this 'rate of change' business. When we acclimate a fish, we're allowing its hydrostatic processes time to catch up to new conditions without causing cell-rupture due to differences in pressure...
What goes on in the tissues of a coral that lives off sunlight and chemicals from the water goes on more slowly, but chemical uptake with one state of affairs in the tissues of the coral and another state of affairs in the surrounding water---given corals don't process as fast as fish---could be causing some unhappy changes. Hence the "my corals like 8.3" on one hand and "my corals like 12" on the other. What the corals wouldn't like is the change, I'm gathering here, although [a surmise, here] rather like keeping your salinity at 1.025 gives you .001 leeway within the 'good' range, keeping your alkalinity somewhere south of 12 might give you more leeway in terms of a sudden rise in alkalinity.

My source in this question maintains that corals tolerate low alk better than they tolerate high alk. But clearly what they don't tolerate at all is a set of changes such as I threw at my tank when I decided to get back to work and correct situtations that had built up over a month. The frags fared worse than my colony, which is still going strong, oblivious to the crisis. And one coral that never had extended polyps is doing so. While the others have RTNed. Boy, these are interesting critters!

Another point: we humans use calendars, and having started my tank last January, I had a lot of items set in my head as 'one year anniversary' projects---read, 'changing out a lotta stuff'. Underline "change" and "lotta." So the human calendar thing didn't interface well with the motto under my sig---make haste slowly. I guess corals don't like anniversaries. ;)
 
I"ve read this thread with interest because I am presently experiencing my third outbreak of RTN in my 9 month old tank. I was told by Greg Hiller that alkalinity was at the heart of my problem because it sometimes slipped below 8. Today when I got up I saw that my yellow milli was half gone. I tested the alk and I got 8.6. I used two kits to make sure. There was no alkalinity change with the last outbreak either. So in my experience, I am doubtful alkalinity shifts are at the heart of this problem. Everything I read contradicts what I read before, and doesn't jive with what I observe in my tank . Most times I read RTN is caused by some sort of stress on the coral . It can be lighting, alkalinity, sudden drop or rise in PO4 or other level, etc. etc. etc.
As far as I can determine, there have been no sudden changes in the water parameters in my tank. I really believe there has to be another cause to this.
 
sometimes they just rtn for no discernable reason.

to answer the question above, my phosphates were undetectable using the merck test at that time.
 
Thanks, twon. Mine tested zip, too, but film algae was regrowing at the rate of every 4 hours, appeared on the glass, so I know I had it in a major way.

I think I'm going to look into kalk as an answer to how to stabilize this a little better. The way I was doing it was fine as long as you tested every few days, but I'm hearing that kalk has the ability to self regulate, by how much the water can uptake, and by how the corals react to mild ph changes.
 
Sk8r, kalk is nice because it doses a balanced amount of Kh/Ca. However, it is still possible to dose more than you need. If your dosing too concentrated of kalk, and your reef is not absorbing that much kh/ca, your levels rise. So just because you use kalk doesnt mean you dont need to test. Kalk does work well until you get to the point where even saturated kalk wont keep up and you dont evap enough water to add more. PH also beccomes an issue when dosing lots of kalk. Kalk will make your PH go up very high if you dose alot of it, espeically if you dose a lot over a short period of time. Either way, dosing kalk would be a better method than using just Kh buffer....
 
THank you, Horace. I do test fairly frequently [once a week] when I'm on track, and this sounds like a good thing. One thing that got me in trouble is not knowing the exact gallonage of my topoff reservoir---I guessed, could be half a gallon off, which can add up over time, and I think I need to get a precise measure. Once I know that, and just watch what I'm doing [and get a battery for the ph meter] I might well be a good candidate for this. I evaporate about a gallon of day in a 52, and my calcium demand was about a tablespoon of Kent Turbo Cal, and my buffer demand has been 2 tsp a day of Kent dkh Buffer---but now that I've lost so many cal-hungry corals, I have to recalculate that demand and start over. 2 tsp per gallon to establish the saturation of kalkwater, or should it be less because I have a pretty high evap rate and a small tank with fewer corals than I had. Maybe I should start with 1 tsp per gallon and see where that puts the levels.
 
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