High Ca and Low Ph

[Patsfann]

Hello,

Started my tank about 3 months ago, and the ph has been low since the start. Its a 75g, with about 90lbs live rock, some carrib sea substrate, skimmer and low turnover rate via the sump about 300gph estimated.

I am using a Pinpoint ph meter that has been calibrated twice, and recently tested with a Salifert Ph test to verify my reading of 7.65 at night and 7.75 during lighting hours.

The Sg is 1.028, temp 78. Amonnia, Nitrite and, Nitrate are all zero. I just tested the Ca (Salifert) and that measures at the highest reading of the kit at 500ppm.

Also I am using Coral Life salt.

I never actually measured a cycle of the tank, the rock was purchased at a lfs and was cured, in his greenhouse. I did speak with the lfs operator and he did not seemed too concerned about the Ph, and advised me to monitor it as is and just watch for trends?

Thanks for your help.

 

[Patsfann]

Forgot to mention that I am using and topping off with RO/DI. And changing 5 gallons per week.

 

[Sponge_Bob]

Making top offs with RO/DI without adding anything to it is the explanation of your problem I think. You are puting in "dead water" in there.

As for the pH, with all your ammo-nitrites-nitrates at 0, I would use Seachem Marine Buffer 8.3. It contains traces elements necessary to your system and not useless additives like aloe vera for instance. Also, I would change salt brand. Coralife is not a reference as far as marine salt goes. If you want, you could switch to Instant Ocean which is probably a bit more expensive but worth it... or go with a brand X salt and see how it goes. I use a brand X salt that's made in Japan and since using it, I have had no problems with my pH. Before, I was using the Red Sea salt, which costs an arm and a leg, and I always had to buffer my pH.

As for your salinity or specific gravity if you will, 1.028 is a bit high. Try to bring it back a bit to 1.027. Also, your tank is cold. Raise the temp to a min of 80°F. I keep mine at 83.5°F because I am making an Indo-Pacific style reef and those are the conditions there.

HTH

 

[Meloco14]

With calcium that high and pH that low I think your ionic balance is out of whack. This happens fairly often with new tanks when you dont have a grasp on how much calcium/alkalinity to supplement. You didnt test your alk, but with your pH that low I bet it is very low. You need to do a large water change and test your params after that. Alkalinity and calcium need to go up and down together. You havent mentioned what you use for supplement, but I recommend a 2 part like two little fishies C balance or B-ionic. Once you do a water change, if your Calcium is still high and your pH and alk are low, you can use the Seachem Reef Builder/Buffer to get your pH and alk to the right level, then just use a 2 part supplement to maintain calc and alk. I also suspect that salt. I would mix up one gallon of new saltwater, let it sit 24 hours, and test it. Check the pH, alk, and calcium and make sure they are all good. HTH

 

[Anonymous]

I think you need to check you alk also. I do not see the need for a large volume water change. Do not does any Ca until the level drops to where you want it the slowly start dosing until you find what your tank needs. Make sure you are dosing a buffer also. I like the seachem reefbuilder and reef calcium combo. Get the powerdered stuff the liquid is way more expensive per dose.

 

[ChrisRD]

I agree with the others about the ionic imbalance likely being a problem here. Although unrelated, I also agree that your SG is a bit high, something like 1.025 or 1.026 is more typical for a reef tank. IME your temp is fine.

Something else to consider is gas exchange. Setups with tight fitting enclosed hoods or a setup in a newer home that is tightly sealed/insulated can suffer from poor gas exchange which can result in an accumulation of excess CO2. This will keep pH levels depressed. Normally a good skimmer will prevent this situation but it may be worth checking.

To test this try taking a cup/bowl of tank water and aerating it for a couple of hours. Test the pH of the sample after aeration. If it's gone up significantly you're probably suffering from a lack of gas exchange. If you suspect the room/house to be poorly ventilated try the aerating the sample in another room or outdoors.

Sometimes simply increasing surface agitation with a powerhead or running the air intake to a skimmer outside the stand (some folks even run them outside the house) can resolve this type of problem.

HTH

 

[Patsfann]

Thanks for your help, If the lfs has and Alk/KH test kit I will pick one up today and get the results to you. Otherwises I will have to mail order. I will do the test that Chris suggests also.

I do need to get more information on dosing, additives,and maintaining an Ionic balance. Being a noob I was thinking that until I get corals, that water changes would suffice.

 

[Anonymous]

I think you need to check you alk also.

Yep.

 

[Sponge_Bob]

I agree with the others about the ionic imbalance likely being a problem here. Although unrelated, I also agree that your SG is a bit high, something like 1.025 or 1.026 is more typical for a reef tank. IME your temp is fine.

According to Dr. Ron Shimek, PhD, the main reason why it is hard to keep a wide variety of corals in a tank is the fact that most people run too cold and with a salinity too low. The indo-pacific region host a huge variety of corals, far more than several if not any other places on the globe. The "norm" that we are used to, which is 1.022-1.025 sp.gr. and temp. at 78-80 is exactly why we can not sucessfully keep certain types of corals for a long period. It's simply too cold or not "salty" enough to sustain them. In the indo-pacific, the average temp. is about 84°F and the salinity around 35 to 37ppt (1.026 to 1.0275).

Here's the link to the full article if you are interested.

http://www.reefs.org/library/members/r_shimek_042799.html

 

[ChrisRD]

1.025 to 1.027 is fine for an SG. A little higher or lower would be OK too, but if you're trying to mimic natural seawater than 1.0264 @ 25 degrees C is one accepted standard. IME/IMO it's not critical what the exact number is as long as you're in a reasonable range. I didn't mean to imply that 1.028 would be problematic as I don't think it would be.

I'm well aware of many of Dr. Shimek's articles and theories and he is by no means the last word on many reefing topics. Many experienced and successful hobbyists don't agree with some of his ideas. Not trying to discredit his work, but many people out there who have a lot more hands-on experience with reef tanks (including other experts in the field) will give you advice/information based on personal experience that runs counter to some of what Dr. Shimek believes.

The Indo-Pacific region is actually quite large and temps vary depending on where you are. According to NOAA data salinities in the region range from about 34 to 36 PPT depending on where you are with average annual temps ranging anywhere from about 25 to 29 degrees C. We regularly see corals in the hobby that are collected from areas in the lower part of that range. Keep in mind too that these are average annual temps meaning that at certain times of year temps are significantly lower with no apparent problems for the corals.

There are different schools of thought on the whole temperature thing and if you do a search you'll probably turn-up a bunch of information as it's been discussed at RDO before. It's an on-going debate, but one thing I can tell you for sure is that it's quite possible to house a wide variety of corals in the mid to high 70s with no issues.

HTH

 

[ChrisRD]

For those interested, here's an article with a differing view on the temp thing with a rebuttal from Shimek and a response to the rebuttal from the author (Harker):
http://web.archive.org/web/20001120...om/fish2/aqfm/1998/mar/features/1/default.asp

 

[Sponge_Bob]

For those interested, here's an article with a differing view on the temp thing with a rebuttal from Shimek and a response to the rebuttal from the author (Harker):
http://web.archive.org/web/20001120...om/fish2/aqfm/1998/mar/features/1/default.asp

Thanks for the reference Chris. Interesting reading indeed. The problem with those articles is that both make some sense and none tend to prove the other is wrong, at least, not totally wrong. Shimek makes a very valid point when talking about Indo-Pacific water parms and that sp. coming from that region should be kept close to that range of temp and salinity. On the other hand, upon reading the article you supplied, it kind of hit me straight in the face that NOT all corals come from this part of the world and that setting them into an Indo-Pacific water condition aquarium might just be detrimental to them.

In my view, Harker puts his finger in his eye down to his elbow when he claims that corals will expand at lower temperature. This is quite stupid of an argument if you ask me. Shimek's article was ALL about giving the best conditions to the corals in order for them to thrive and grow at their peak. It's much like putting a small fish in a medium tank and do the same with the same kind of fish but in a larger tank and see how fast they grow. IME, the fish in the larger tank will ALWAYS grow more rapidly than the other. At least, in FW. I do not have enough experience to debate this point in a SW tank, but logic dictates that the same must be true.

On the other hand, Harker does make a valid point in terms of increased bioload being proportional with temp. increase. Having a chemistry degree, I know that most chemical reaction are accelerated by an increase in temp. Now, having a brand new tank (Dec 2005), setting it at 83.5°F like I did might not be helping me at all, in terms of Nitrate reduction.

Bleaching and infectious disease are not much of concern so far for me and I don't think that Shimek would be stupid enough to actually advise people to set their temp to a degree where bleaching would occur. But, I will keep it in mind.

In conclusion, I am a bit ambiguous about who's theory to believe and who to rely on. Shimek, who's a PhD and made some valid points, or Harker, who did make some valid points as well? Given my lack of experience and knowledge, I have no other choice but to cut the pie in 2, ie. set my temp. back a bit and see how it goes. I will therefore reduce my tank temp. to 81°F. As for my salinity, I will target 1.025 - 1.026 from now on.

Thank you again Chris for a very educative and interesting read. I owe you one more! Gawd... this will cost me a bundle when next x-mas comes!!! :lol:

 

[Anonymous]

One thing to consider when keeping the temp above 80F is that even thou the critters can tolerate and some even thrive it does not give you much wiggle room if/when something goes wrong. My preference is between 78 and 80F.

 

[Patsfann]

I just got my Salifert KH/Alk test and here are the readings,
KH 12.2 (in dKH) and Alk 4.34 meq/L. The other tank paramater are as outlined in the original post.

Also I am airating a container of tank water and will measure the ph in the a.m. Any advice about these readings? I do have Seachem reef buffer and reef builder but have not started dosing yet.

 

[ChrisRD]

Your alk sounds fine (actually a bit on the high side).

Check the pH of the aerated water tomorrow and see if has risen significantly.

 

[jumpincactus]

Dang Chris you really do seem to have a good handle on this hobby. But dont get the Puffer fish thing going and let it go to your head LOL

No really all BS aside I really look forward to your input on this board. You seem to be able to usually back up what you say with great links and articles. The one we are discussing was awesome. Although I would have to agree that I am a bit confused on who's theories are accurate.

What is interesting here is with given how temperatures work in the ocean and even in a closed system it is clear that the deeper on the reef a coral is found the cooler the temperatures in the ocean. So in stocking our tanks we would have to consider the actual area of the reef the invert was harvested so we could simulate placing it at the right depth in our tanks.

What I am now asking myself is this, in knowing that the ocean waters are cooler the deeper you go then would not the same be true of our closed systems. Meaning where is the best place to actually take our temperature readings from?

See where I am going with this?? would not say a Montipora coral that is say found at 30 meters depth do better in a deeper place in my tank as opposed to stocking it near the top with strong halide lighting. Even though our systems are small and closed would not the water temperature vary at different depths in the tank. Or am I splitting hairs at this point?

So where is the best place to get overall tank temperature readings or does it even matter.

 

[ChrisRD]

I'm glad my babbling has been of some help to someone! :wink: This board is a great informational resource and there are a lot of folks around here who know a lot more about the hobby than me which is one of the reasons I like spending time here. No matter how long you're in this hobby there is always something else to learn!

As for the temp thing - considering the small volume and strong circulation in a reef aquarium, normally there won't be any significant differences in temps at various locations in the tank.

As for trying to match the exact conditions of the locations our corals are collected from, it would be nice if we could. Unfortunately, since the average reef aquarium is usually a mixed bag of animals from mixed locations we can't really replicate all those environments in one small space very well. To further complicate things we don't really know the exact conditions our animals were collected from.

If you setup a system that is modeling a certain biotope it would be possible to narrow all that down a bit and make the idea more attainable (which is exactly why some folks advocate this approach).

Fortunately most of the corals that are popular in the hobby are very adaptable to a fairly wide range of conditions so if properly acclimated tend to do fine in our systems as long as we stay within some basic parameter ranges.

But that said, it's a fairly complex topic and we should probably start another thread to get into it any further. We're sorta highjacking Patsfann's thread. :wink:

 

[jumpincactus]

You know Chris after reading the Shimeck and Harker article I am wondering........... Since Harker states that he has kept reef tanks for approx 8 years he says that he has kept his temperatures in the mid 80 degree range and at times have peaked at 93 with no adverse effects on critters. Am I to believe that the purchase of a 560.00 chiller is an un neccassary addition to my reef tank. ? The Seattle weahter is moderate at best even in the summer months. Yes it true that I dont have central air cond. So would I be ok without the chiller and just use a fan over the tank or sump in the summer??

 

[jumpincactus]

Dohhhhhhhhhhhhhhhhhhh I have a history of hijacking. Sorry Patsfann. I blame my ADD

 

[ChrisRD]

It's not necessarily a certain temp that causes problems, but also how much swing. In other words if you normally run your tank at 84 and it hits 88 one day in the summer it probably won't be an issue. If you normally run at 76 and it hits 88 you're probably going to see some bleaching.

It's certainly possible to setup the tank so that a chiller is not required (I've never had to use a chiller) but it's hard to give a definite answer as there are many variables that come into play. Some factors would include ambient temps, ambient humidity levels (lower = more evaporative cooling potential), what sort of pumps you're using (some transfer lots of heat, some very little), what sort of lighting you're using and how it is setup, etc.

Don't hesitate to start a new thread if you want to discuss in more detail. :wink: