Need help, Randy are you out there

[mcfa2403]

After watching my corals for months I realized something is significantly limiting corals in my tank. Colors are good and the health of most of my corals is there but some corals are significantly struggling and growth isn't what it should be.

The tank is 48" x 20" x 18" lit by 2 kessil A350 on the sides and a Hydra 52 all lifted ~15" from the water surface. Acropora in the center of the tank lower light species on the sides. The tank has a moderate-high bioload and is a mixed reef with roughly equal parts LPS (mostly euphyllia) to SPS (mostly Acropora). Coloration is there in the Acropora so I doubt it is a lighting issue. Flow is powered by MP40 and Tunze nano turbelle and 750gph from the return and appears to be more than enough. Polyp extension is great on all acros.

Parameters:
Salinity 35ppt - Milwaukee Digital Refractometer
Nitrates stay between 5 and 10 ppm - Salifert
Phosphates < .3 ppm - Salifert
Alkalinity 9.6-10 dKH - Salifert
Calcium 430-440 ppm - Salifert
Magnesium 1320-1350 ppm - Salifert
pH 7.7-7.9 - Salifert

Dosing method is the Tropic Marin 3 part dosing powder injected via Bubble Magus T11. I have the pumps set to dose based on the recommended Tropic Marin ratios and use alkalinity as my baseline for maintenance. Without dosing Alk drops ~.8 dKH per 24 hours so I assume growth is occurring but based on what it could be it feels off.

Of other note the only montipora I have success with is a Jason Fox Mystic sunset (not sure which species this is) which has grown exponentially, my montipora Caps look healthy and exhibit great polyp extension but haven't even come close to doubling in size in over a year, and plating species as well as digitata slowly turn grey and struggle. Birdsnest will form multiple growth tips and look to grow but slowly succumb to STN. Chalices seem to be hit or miss but I assume that could be tank conditions, the same is true of acans.

With about 60lbs worth of dog, myself and my wife (we spend about 12 hours apiece physically in the apartment each day) in a 1200 sq ft apartment I assume that excess CO2 is some of the issue. When I left a sample outside for 3 hours before testing it test .3 points higher (about 8). I am trying to get a hold of a probe to get a more accurate test.

I do attempt to leave windows open for a few hours every week but with yappy dogs in an apartment (thanks wife) this is hard to do. I would rather not mess with try to run a hose from the skimmer to the window for several reasons. I have used kalkwasser in the past but for me it is difficult to manage as my tank is rimless with a high surface area and my sump has a 36" x 18" surface area so topping off with kalkwasser has been difficult to stabilize (plus makes the dosing system much more difficult). I know this is me being difficult here but wasn't sure if there was another way (I already run my calc/alk higher than most but would be willing to push higher if reccomended).

I was hoping perhaps you could shed some light on to the issue as perhaps it is not even a pH issue.

Extra info:
Skimmer is reef octopus 150SSS
I have discontinued running carbon in my tank (results are the same)
Skimmer and dosing pump are the only equipment I run
Total Water Volume is 75 gallons +/- 2 gallons (calculated using salinity)
No stray voltage present
Corals seem to periodically go through rapid growth phases and then stop

 

[Ron Reefman]

Does Randy still check in here? I know he's active on a different forum.

 

[snorvich]

Of course, we have other expert chemists who will also check in here when they can.

 

[CHSUB]

not randy, but?

ask people who grow corals, TOTM, or direct studies involving no3 levels and sps' health! 99% will state no3 needs to be very low <1.0 ppm. take a look at Marubini and Davies' (1996) study about no3 levels and skeletogenesis. Forget about the "guy" on RC whose tank been setup for 6 months and says my sps' are great and no3 is 10 ppm. Lower no3 to near 0 on Salifert and get back to us on the results! i bet you will be happy....

 

[mcfa2403]

I am happy with any chemistry expert, I hope I didn't offend anyone!

I understand that many tanks run with low nutrients have incredible success but so has Rich Ross with much higher nutrients. There have also been peer reviewed studies (albeit on ocean colonies) suggesting that "high" nutrients effects on coral growth are statistically irrelevant as they do not fall outside the realm of random chance whether positive or negative (high by our standards not sky high obviously). I tend not to mimic other peoples tanks too much as each system will vary drastically based on microorganisms, flow, rock structure, outside environment and so much more. There are just too many variables, while I do try to keep my nitrates lower I feel that in my system my corals respond more positively to the excess feedings of rotifeast and oyster feast that is driving the number up. I have tried 3 month periods of each and so no difference that swayed me significantly as to one being better than the other except I prefer the increased polyp extension observed with the extra feeding. (The tank has been up for just over 2 years now)

In 3 months of low nutrients I saw no change in the corals that have been struggling. I tend to work under the assumption of correlation does not equal causation. However, I appreciate the suggestion and did actually try that 3 month period (kept every other variable constant as best I could) based on TOTM threads.

 

[CuzzA]

I had a similar problem as you. Nitrates at 5-10 and running alkalinity high. For some reason this is not good. Choose one or the other. Either reduce nitrates or reduce your bicarbonate. I chose the easier option and lowered my dKH to around 7 (Natural Sea Water). Growth immediately took off and hasn't looked back. Necrosis events stopped. I've never had a problem with color, but I suspect that is because my tank is heavily stocked and I feed quite a bit, thus nitrates at ~5. I believe if your corals are getting energy from food then they require less energy from zooxanthellae, which results in less symbiotic algae within the tissue, ultimately allowing the corals to exhibit their beautiful colors.

 

[mcfa2403]

CuzzA, the increase in Alk was actually a recent event. I had been running it 7.6-8 but recently raised it based on the reefkeeping article about pH problems. I'm hoping this will yield some results as it has only been 3 weeks and I plan to give this option more time before making other changes. I am trying to plan my next step in case this does not solve the issue.

Unfortunately I screwed up and made another change around the time I upped the alk, I removed a plastic tub I used to cleanly house my sand bed for my refugium (just took the whole refugium offline). This was kind of stupid on my part as I try to only make one change at a time so I can track any issues that arise.

The final thing I should note is that the Necrosis has only really been isolated to a few species (montipora digitata, montipora capricornis, and achalice of which I am unsure of the species). Some of the other species seem to grow in odd surges (mostly just specific acro species) and the one acan I have just doesn't seem "happy". I have had two BTA split in the last month but everything else appears to do just fine.
I started this thread in the SPS forum as well and included several pictures.

Thanks again to everyone trying to help, I hope I don't come off as rude as I certainly do not intend to be.

 

[CHSUB]

I am happy with any chemistry expert, I hope I didn't offend anyone!

I understand that many tanks run with low nutrients have incredible success but so has Rich Ross with much higher nutrients. There have also been peer reviewed studies (albeit on ocean colonies) suggesting that "high" nutrients effects on coral growth are statistically irrelevant as they do not fall outside the realm of random chance whether positive or negative (high by our standards not sky high obviously). I tend not to mimic other peoples tanks too much as each system will vary drastically based on microorganisms, flow, rock structure, outside environment and so much more. There are just too many variables, while I do try to keep my nitrates lower I feel that in my system my corals respond more positively to the excess feedings of rotifeast and oyster feast that is driving the number up. I have tried 3 month periods of each and so no difference that swayed me significantly as to one being better than the other except I prefer the increased polyp extension observed with the extra feeding. (The tank has been up for just over 2 years now)

In 3 months of low nutrients I saw no change in the corals that have been struggling. I tend to work under the assumption of correlation does not equal causation. However, I appreciate the suggestion and did actually try that 3 month period (kept every other variable constant as best I could) based on TOTM threads.

increased feeding and no3 levels are two different things and entirely unrelated, except that increased feeding may increase no3 levels if, and only if, export is not sufficient. Ross seems to be the 1% and more importantly, he also runs po4 sky high. i perfer to follow the 99% with regards to no3 and feeding: low nutrients and, in my case, a lot of fish with 5 a day feedings!!!!

 

[GPHowell]

Parameters:
Salinity 35ppt - Milwaukee Digital Refractometer
Nitrates stay between 5 and 10 ppm - Salifert
Phosphates < .3 ppm - Salifert
Alkalinity 9.6-10 dKH - Salifert
Calcium 430-440 ppm - Salifert
Magnesium 1320-1350 ppm - Salifert
pH 7.7-7.9 - Salifert

I have almost identical parameters in my 400 L, two-year-old tank, except alkalinity is about 11 dKH and NO3 is <0.5 ppm. I've re-checked all parameters as of yesterday with brand-new, Salifert kits.

I, too, observe sporadic growth of corals although they all display good colouration and polyp extension. I've also been wondering if the pH is causing a problem.

A more serious issue is that I have only purchased 2 fish in the last 6 months (long-nose butterfly and a Potter's angel) from a very reputable LFS and both have died within 4 hours. I've been keeping fish for 20 years and have never had anything like this occur before- it's really confusing. All of the other fish in my tank are healthy and vibrant so I don't see how it could be a toxin or toxic-level of a dissolved substance. I can only think that one of my water parameters is significantly different to my LFS which is shocking the new fish and killing it. The only parameter I have that is "non-standard" is the pH.

My pH is routinely 7.7-7.9 (depending on when I measure it during the day) using a pH probe that is calibrated properly. I don't run a sump/skimmer and the aquarium is not near a window so I'm not sure how I would go about reducing dissolved CO2 levels (if indeed that is causing the pH issue).

I've though about adding a non-carbonate/borate base to raise pH- calcium or sodium hydroxide for example - but these are very strong bases with no real buffering ability which is making me a little cautious.

 

[blanden.adam]

I wonder, why is it that you think growth isn't what it should be for your corals? Sometimes corals, particularly SPS, go south quickly for no apparent reason when the rest of the tank is doing fine. It also takes some SPS corals a while to adapt to a new tank. Sometimes corals just kinda sit there for a year and do nothing, then start growing a lot. They're funny like that.

Your phosphate is quite high, which is a known inhibitor of calcification (most people try to keep phosphate <0.08 ppm or so). Your nitrate level is on the high side, but a nitrate level of 5ish isn't so bad and many people report better growth with single-digit ppm levels of nitrate. The rest of your parameters look fine. pH might be a little low, but any test kit measurement I don't trust to more than about 0.5-1 pH units (they really aren't that accurate).

So, from the information I can see (as I haven't been watching your tank for years), I'm unsure if you actually have a problem, but if you have a problem and it's because of tank chemistry, you might try lowering your phosphate or bumping up your pH. Apart from that, if there is a problem, it's not in the chemistry you are keeping (assuming the levels are all stable).

 

[blanden.adam]

I have almost identical parameters in my 400 L, two-year-old tank, except alkalinity is about 11 dKH and NO3 is <0.5 ppm. I've re-checked all parameters as of yesterday with brand-new, Salifert kits.

I, too, observe sporadic growth of corals although they all display good colouration and polyp extension. I've also been wondering if the pH is causing a problem.

A more serious issue is that I have only purchased 2 fish in the last 6 months (long-nose butterfly and a Potter's angel) from a very reputable LFS and both have died within 4 hours. I've been keeping fish for 20 years and have never had anything like this occur before- it's really confusing. All of the other fish in my tank are healthy and vibrant so I don't see how it could be a toxin or toxic-level of a dissolved substance. I can only think that one of my water parameters is significantly different to my LFS which is shocking the new fish and killing it. The only parameter I have that is "non-standard" is the pH.

My pH is routinely 7.7-7.9 (depending on when I measure it during the day) using a pH probe that is calibrated properly. I don't run a sump/skimmer and the aquarium is not near a window so I'm not sure how I would go about reducing dissolved CO2 levels (if indeed that is causing the pH issue).

I've though about adding a non-carbonate/borate base to raise pH- calcium or sodium hydroxide for example - but these are very strong bases with no real buffering ability which is making me a little cautious.

Not to hijack, but you aren't just tossing the fish into your DT when you get them home are you? There are many ways to avoid stressing fish due to different water parameters (the primary one being salinity level), the best ways involve using a lower-salinity quarantine and slowly increasing the salinity over the 30 day QT period. LFS often keep a lower salinity level for fish than is required for reefs, and going from a low salinity (say sg 1.018) to high salinity (1.026) can kill a fish in short order. But, if you think it's a problem it might be worth another thread or reading this: http://reefcentral.com/forums/showthread.php?t=1939508, and this: http://www.reefcentral.com/forums/showthread.php?t=2185929.

 

[mcfa2403]

I am an idiot, no wonder everyone keeps questioning my phosphate. It should read less than 0.03, I am sorry about the confusion!

 

[Reefstarter2]

From experience playing with high phos in my own systems that is your limiting factor. Once they get at or below.1 things start to get happy again

 

[mcfa2403]

From experience playing with high phos in my own systems that is your limiting factor. Once they get at or below.1 things start to get happy again

Yeah I mis-typed earlier it should read that they are less than .03

 

[acesq]

From the sound of things you know your way around critical analysis better than most so you are likely to figure "it" out (if there is an "it" there) before anybody else does. Your chemistry is well within acceptable parameters, with the pH on the low side. Have you tried a Triton test? That may disclose an imbalance of some trace element that the montis need more than the SPS.
Also, consider the quality of your make-up water. I suffered through a long period of poor sps health that I determined to be due to chloramine breakthrough in my RO/DI.

 

[CHSUB]

Yeah I mis-typed earlier it should read that they are less than .03

if you watch Ross' entire presentation you will see he briefly discusses low po4 and high no3, and he states his experience about it producing unhealthy sps'.

 

[mcfa2403]

if you watch Ross' entire presentation you will see he briefly discusses low po4 and high no3, and he states his experience about it producing unhealthy sps'.

This is something I have considered and I still do want to try to bring my nitrates between 2.5-5 (preferably 2.5 but with color differences being so slight I usually categorize it by range). I am guessing the best way to do this is likely by increasing my live rock (or marine pure) content in my sump so as to remove more nitrates at a higher proportion than phosphates.

 

[mcfa2403]

From the sound of things you know your way around critical analysis better than most so you are likely to figure "it" out (if there is an "it" there) before anybody else does. Your chemistry is well within acceptable parameters, with the pH on the low side. Have you tried a Triton test? That may disclose an imbalance of some trace element that the montis need more than the SPS.
Also, consider the quality of your make-up water. I suffered through a long period of poor sps health that I determined to be due to chloramine breakthrough in my RO/DI.

I have suspected chloramine but this is the only tank suffering this issue using the same water. I have considered doing the Triton test I was just hoping that using Tropic Marin Salt and Tropic Marin 3 part dosing would prevent this from being the case. However, this now seems the most logical next step as it does not effect my methodology of altering variables.

Oh, and I appreciate the compliment I do try to be as scientific as possible in my approach. I feel that rushing through changes leads to a lack of understanding of the root issue or leads to a whole other issue.

 

[acesq]

I have suspected chloramine but this is the only tank suffering this issue using the same water. I have considered doing the Triton test I was just hoping that using Tropic Marin Salt and Tropic Marin 3 part dosing would prevent this from being the case. However, this now seems the most logical next step as it does not effect my methodology of altering variables.



Oh, and I appreciate the compliment I do try to be as scientific as possible in my approach. I feel that rushing through changes leads to a lack of understanding of the root issue or leads to a whole other issue.

Good luck! Keep us posted with your journey to figure it out. (You might want to run a fresh air line to your skimmer or risk the wrath of you neighbors by opening a window -- maybe with a window fan to drown out the yapping --just to eliminate that nagging issue)

 

[tmz]

The PO4 at around .3ppm seems high enough to alter the calcification process; ah ok reread ; 0.03 is certainly low enough( not sure a reading on the salifert test at that low a level is easily discerned though) .The NO3 also seems high; IME some sps fair poorly at those levels particualry seriatorpora.

However, the lower pH( higher CO2) might actually be helping overall given the higher NO3 as the study suggests . I don't know that since I don't run my aquariums that way but I suppose it's possible you might want even higher PO4 to enable the zoox to use the NO3.May be some iron too. This is an abstract from the study noted ion post #4


Zooxanthellate colonies of the scleractinian coral Astrangia poculata were grown under combinations of ambient and elevated nutrients (5 µM NO₃⁻, 0.3 µM PO₄^{− 3}, and 2 nM Fe^{+ 2}) and CO₂ (∼ 780 ppmv) treatments for a period of 6 months. Coral calcification rates, estimated from buoyant weights, were not significantly affected by moderately elevated nutrients at ambient CO₂ and were negatively affected by elevated CO₂ at ambient nutrient levels. However, calcification by corals reared under elevated nutrients combined with elevated CO₂ was not significantly different from that of corals reared under ambient conditions, suggesting that CO₂ enrichment can lead to nutrient limitation in zooxanthellate corals. A conceptual model is proposed to explain how nutrients and CO₂ interact to control zooxanthellate coral calcification. Nutrient limited corals are unable to utilize an increase in dissolved inorganic carbon (DIC) as nutrients are already limiting growth, thus the effect of elevated CO₂ on saturation state drives the calcification response. Under nutrient replete conditions, corals may have the ability to utilize more DIC, thus the calcification response to CO₂ becomes the product of a negative effect on saturation state and a positive effect on gross carbon fixation, depending upon which dominates, the calcification response can be either positive or negative. This may help explain how the range of coral responses found in different studies of ocean acidification can be obtained.

FWIW, I do not have the problems you noted with NO3 around 0.2ppm( per salifert) ,PO4 in the 0.02 to 0.04ppm range ( per hanah 713) and pH daily siwng 8.15 to 8.35( per pinpoint and milwaukee monitors with alk around 9dkh in a heavily fed system ;been solid for over 6 years this way .