Low ph and calc with high alk

[JWarren]

Ok Lynn,

Sorry about taking so long to prepare this post.

I am going to attempt to break this down as much as I can without getting too technical on ya. Just look at it as a refresher course if you already know this stuff.

pH is a measure of the acidity or alkalinity of a solution.

You are either acid or you are soap, if you are not either, you are neutral at a pH of 7.

Here are a couple of charts to help you understand pH.

ImageH scale.png - Wikipedia, the free encyclopedia
ImageH scale 2.png - Wikipedia, the free encyclopedia

Alkalinity is basically a measure of the capability of the water to resist changes to pH from the addition of acid. It is effectively the buffering capability of the water. In our aquariums we measure total alkalinity which is the amount of acid required to convert all the bicarbonate and carbonate into carbonic acid. The higher the alkalinity is, the more acid that is required to lower the pH so that all the bicarbonate and carbonate becomes carbonic acid.


Alkalinity is made up of a number of components, with bicarbonate being the largest contributor. The other components, in order of representation in normal seawater, are: carbonate, borate, silicate, magnesium monohydroxylate, hydroxide and phosphate. In an aquarium, the ratios of these components may vary.

The most obvious reason for maintaining alkalinity levels is to stabilize the tank pH. As alkalinity is a buffer, the pH of the tank will shift less if the alkalinity is high. In your case the elevated CO2 level has lowered your pH but your water is still buffered sufficiently. Driving off the excess CO2 with an air stone, skimmer or increasing the amount of plants in the fuge which, consume CO2, will help.


There is a much more important reason for alkalinity in a reef tank. The main component of alkalinity is bicarbonate and bicarbonate is actively used by calcifying organisms ( stony corals, molluscs, coralline and other calcareous algae, as well as sponges). Alkalinity must be kept at a sufficient level to ensure these organisms can get enough bicarbonate. The alkalinity of a tank with a lot of calcification will drop quite rapidly.

Normal seawater has an alkalinity around 2.4 meq/L (Pilson, 1998). For a reef tank it is usually wiser to keep the alkalinity above 3.0 meq/L simply because it can drop quickly while organisms are calcifying. There are a lot of reefers who maintain levels of alkalinity around 4 meq/L due to the great consumption rates of a heavily stocked tank of stonies.

So, what to do….

Knowing the above info, the next step for me, would be to drive off the CO2 and since the calcium and pH are low, a good addition to the tank would be Calcium Chloride. The Calcium Chloride will help to raise the pH as well as lower the carbonates attributing to the high alkalinity.

If you have a pH headed toward the acid range, the chloride in the CaCl will help to bring it back up. If you take a look at the pH chart you will see that Chlorine has a pH of 13. The chloride will become the increaser, to help the pH climb. The change will be gradual, but with water changes the change will be sped up a bit. I’m not sure if Turbo calcium is Calcium Chloride or even if it contains calcium chloride, maybe someone else will know.

Hopefully reading this will help you a bit. I could add a lot more to this but my attempt was to try and keep it very simple for ya.

 

[sasquatch]

John, I may be completely out to lunch on this but my concern with artificially raising ph "with an existing problem" is the chance of an abrupt rise in ph if the original problem resolves itself.

 

[prow]

lynn, dosing a ph issue with buffer might have kept the ph up for a little while but futher dosing with buffer probably caused some Ca+ to precipitate out of solution. maybe the reason your Ca+ is so low and alk so high. so with that,

It says little to no effect on the ph so at least it shouldn't make it worse.

well, dont try to fix your ph right now. more important to get the Ca+ and alk balanced. so dont stop if the ph changes some.

Unless somebody says otherwise I think I am going to add calcium and see if that helps or hurts the ph.

good on dosing Ca+ but dont pay too much attention to the ph, unless it gets down to 7.6.

it goes down then obviously I will stop but if it stays the same or goes up I will keep adding the calcium.

:smck: no, no, nobeat_dead_horse

I am hoping that by fixing the alk/calc imbalance that it will help or at least not hurt the ph.

likely to correct it.

Meanwhile I am going to try the aeration again and see if that helps the ph. I am afraid to try too many things at once or I may make things worse.
Meanwhile the Marine Buffer is in the garbage can never to be used again since it seems to have caused this whole mess.

Marine Buffer or seachems reef buffer is ok to use, but use only if both your alk and ph are low. for low alk and good to a little low ph seachems reef builder is the ticket. raising just Ca+ for a quick fix turbo Ca+ is good. i would suggest you use seachems adv. Ca+ as it contains stronitium and Mg in balanced ratios to Ca+.

ok, why i say no to stopping your dosing of Ca+ because ph. as you raise your Ca+ your alk will get used up. your ph may go up some or down some, depends when test it after dosing. with Ca that low and alk that high i would dose a lot of Ca+, dont worry to much on overdosing, it will percipitate and you might waste a little Ca but no big. but do watch your alk close as you raise your Ca+. much of your bicarb has been converted to carbonic acid, adding Ca will help take the carbonate out of that. and that will help the ph. just focus on getting things balanced, if worst comes to worst do a back to back 50% water change, with each batched mixed to good levels. then see were your at.

 

[Boomer]

I need to fix some things and I did not get them all


Knowing the above info, the next step for me, would be to drive off the CO2 and since the calcium and pH are low, a good addition to the tank would be Calcium Chloride. The Calcium Chloride will help to raise the pH as well as lower the carbonates attributing to the high alkalinity[

The chloride ion has not effect on pH or Alk. The calcium ion if anything will drop the pH even further, for as the Ca++ from the Calcium Chloride may attach itself to a CO3-- and form Aragonite or Calcite. This drops the Alk and thus, may also drive down the pH.

CO3-- Ca ++ + CO3-- > CaCO3 = solid Calcite/Aragonite, called abiotic precipitation

Marine Buffer or seachems reef buffer is ok to use

NOT Marine Buffer it will really mess up a tank that is being dosed with sups. It is for FOT, even SeaChem will tell you that. This buffer will more or less off-set the normal seawater chemistry. It can cause lots for problems of not being able to dose things and get them where you want them. As the rules are different. Normally the only cure is 2 -50% or greater water changes a day apart. It is great stuff for a FOT and I always recommend it for them. The stuff also skews your alk test kit waaaaay off as there is crap loads of Borate in it. Meaning it reads way to high. Your real "Carboante Alk may only be 3.5 meq / and not 4.5 meq/ l .


as you raise your Ca+ your alk will get used up.

No it won't that is 95 % myth and often misunderstood issue. You can get the calcium very high without it affecting the Alk at all. This "get used up" deals with if animals, like corals or when abiotic precip is taking place and that rate of drop is 20 ppm / 1 meq / l ALK. If you have animals that use little Ca++ it will continue to climb and the Alk will still fall as it is used up in other reactions such as neutralizing acids. At time one can add large amounts of Alk to get the Ca++ down, it is another method we do not really recommend. On the same note one can add crap loads of Calcium Chloride to drive the Alk down and we don't recommend this either. This is all part of abiotic precip which is controlled by the Ca++, Mg++, Ph and Alk. For example with a low pH of around 8.00 a low Alk ~ 2.00 meq/ l one can raise the Ca++ over 800 ppm with CaCl2 with no precip. Precip actually starts, in theory, around a pH of 8.2, Alk 2.5 when the Ca++ is ~800. As the Alk rises above that the amount of Ca++ becomes less with increasing Alk or pH, i.e.., precip @ ~pH 8.2, Ca++ 410 and Alk 5 meq/l

Lynn

You DO NOT add buffers for pH, they are for ALK. If one has a low Alk and low pH then one can use baked baking soda to adjust it. Kalk should be used to raise the pH only when it is low or to fix a CO2 issue OR you need to see why, find out why, you have a CO2 issue and fix it first.

 

[JWarren]

Hey Boomer,

Thanks for the kickback!

Some of my research came from reading some of RHF's stuff on imbalances.

I refer to "Corrections for Zone 3" half way down the page.

Solving Calcium and Alkalinity Problems by RANDY HOLMES-FARLEY

I have fallin into this same boat that Lynn is in in the past and gave Randy's suggestion a try and it did work.

The problem I have experienced with adding Kalk to adjust the imbalance is Kalk adds a balance of alk and ca. Although it dosent hinder the alk from falling, it just takes longer for it to equalize. I do agree that it will raise the pH, but like you said with the elivated CO2 level, this would need to be corrected.

 

[prow]

I need to fix some things and I did not get them all


Knowing the above info, the next step for me, would be to drive off the CO2 and since the calcium and pH are low, a good addition to the tank would be Calcium Chloride. The Calcium Chloride will help to raise the pH as well as lower the carbonates attributing to the high alkalinity[

The chloride ion has not effect on pH or Alk. The calcium ion if anything will drop the pH even further, for as the Ca++ from the Calcium Chloride may attach itself to a CO3-- and form Aragonite or Calcite. This drops the Alk and thus, may also drive down the pH.

CO3-- Ca ++ + CO3-- > CaCO3 = solid Calcite/Aragonite, called abiotic precipitation

Marine Buffer or seachems reef buffer is ok to use

NOT Marine Buffer it will really mess up a tank that is being dosed with sups. It is for FOT, even SeaChem will tell you that. This buffer will more or less off-set the normal seawater chemistry. It can cause lots for problems of not being able to dose things and get them where you want them. As the rules are different. Normally the only cure is 2 -50% or greater water changes a day apart. It is great stuff for a FOT and I always recommend it for them. The stuff also skews your alk test kit waaaaay off as there is crap loads of Borate in it. Meaning it reads way to high. Your real "Carboante Alk may only be 3.5 meq / and not 4.5 meq/ l .

all this i think i said but in a different way, maybe not so clear of a way. but still i agree. exp on the water changes---lynn the water changes will get you back to square one, it will be much easier to correct the original issue after, may end up fixing it without any futher adjustment, then star dosing with kalk esp if atmospheric CO2 is the issue. o keeping the temp lower 78ish will help as it calms down metobolic rates some (reduces O2 demand, thus reduces CO2 saturation levels)

as you raise your Ca+ your alk will get used up.

No it won't that is 95 % myth and often misunderstood issue. You can get the calcium very high without it affecting the Alk at all. This "get used up" deals with if animals, like corals or when abiotic precip is taking place and that rate of drop is 20 ppm / 1 meq / l ALK. If you have animals that use little Ca++ it will continue to climb and the Alk will still fall as it is used up in other reactions such as neutralizing acids. At time one can add large amounts of Alk to get the Ca++ down, it is another method we do not really recommend. On the same note one can add crap loads of Calcium Chloride to drive the Alk down and we don't recommend this either. This is all part of abiotic precip which is controlled by the Ca++, Mg++, Ph and Alk. For example with a low pH of around 8.00 a low Alk ~ 2.00 meq/ l one can raise the Ca++ over 800 ppm with CaCl2 with no precip. Precip actually starts, in theory, around a pH of 8.2, Alk 2.5 when the Ca++ is ~800. As the Alk rises above that the amount of Ca++ becomes less with increasing Alk or pH, i.e.., precip @ ~pH 8.2, Ca++ 410 and Alk 5 meq/l

this though i dont agree with. the abiotic precip yeah. but here we are not talking about a voided tank or even a new tank. seeing Lynn around here for awhile i am "assuming", i know bad word, that her tank is not new. she has mentioned she does have corals aswell. in a 90gal (again "assuming" this the tank with the issues) her Ca+ is 325, at that level calcium uptake is some what depressed or better said inhibited/slowed via Ca+ channels remaining closed. once Ca+ gets into the normal ranges those channels open, consequentially, once these pathways are open and Ca+ flows, alk gets used up along with it. IMO, dosing in this tank to get the Ca+ up to 400ish, will eat up some alk (440ppm to balance, a 120ppm increase in Ca+ to balance). just the coraline alone will have enough of a demand to show its effect on the alk as Ca+ levels rise, in this case. also as the ph goes up alk get used up, futhermore, calcification rates in her corals and coraline will increase along with increased ph, so a even more rapid decline in alk will result as things begin to balance to acceptable levels. i do agree though, if this was just mixing a solution, slowly, you are correct no alk will get used, but this in not the case here. however, i do think if she doses with CaCl- and shots for 400ppm the resulting effects on alk may very well balance thing out to something on the order of a Ca+ level of 400ppm with a alk of 2.0meq/l. thats a 2.0meq/l decrease in alk for a 60ppm increase in Ca+. it should be close to thoughs levels after her dosing CaCl-.

 

[bluespotjawfish]

Good luck Lynn on resolving this!

Did you test your new water yet?

 

[lcstorc]

Still in Miami so water changes have to wait for the weekend. I can get Frank to buy whatever supplement and dose appropriately but I doubt I can talk him into it after work when everything is actually looking good in the tank. I can get him to start mixing water but I need to figure out what salt I should use since I was wrong about the Oceanic and apparently it is high alk instead of the low alk I was looking for.
The tank with the issue is the 125 which has been up for 3 years. I do not have stony corals but do have 3 clams. Mostly it is a softie/fish tank. A couple of LPS but not much since my Chevron likes to munch on them.
Frank has dosed Calcium right before the tests and again last night. I will get him to run tests before and after he does anything tonight. We have not seen any calcium storm in the tank and I really don't know where the CO2 would be coming from. However several people I respect have insisted so this weekend I will be sure to open everything up with fans etc and see if that makes a difference. Sounds like it should so I certainly will give it a try. I did have Frank open the windows and there are already several fans in the stand and across the top of the water. I can have him aim the powerheads up a bit as well to add more surface motion. You mention a ph of 7.6 as a place to get worried and it is 7.7 in the evening right now. I have been afraid to look in the morning but I am sure it is lower since I have little macro and no light in my fuge. (It broke long before the problem and I just haven't replaced it yet.)
Thanks everybody for the help. If I get good tests on the NSW I will do a significant water change this weekend and see if it helps as well.

 

[Boomer]

John

I refer to "Corrections for Zone 3" half way down the page.

Yes I know and when I said "we" do not recommend this that means me and Randy They method of using CaCl2 or buffer to fix these was the "invention" of Dr Craig Bingman, who use to be our "Randy years ago. If you check our chem forum on RC you will see a sticky on "reef chem articles" and you will find Craig's name way down, where he is the author of a allot of "Randy" type articles. Craig is still the editor of many of the articles in the on-line magazines.

Yes, Kalk will fix the CO2 but it needs to be fixed the right way and not have a band-aide. Kalk is fine for small pH increases

Prow

I hate to tell you this but you are in error and disagreeing with the facts of chemistry, which Randy has written about them extensively. I'm quite familiar with Lynn and her tank


at that level calcium uptake is some what depressed or better said inhibited/slowed via Ca+ channels remaining closed. once Ca+ gets into the normal ranges those channels open, consequentially, once these pathways are open and Ca+ flows, alk gets used up along with it. IMO, dosing in this tank to get the Ca+ up to 400ish, will eat up some alk (440ppm to balance, a 120ppm increase in Ca+ to balance)

Often not the issue at all when a system is in an ionic imbalance. It has nothing to do with "channels" being closed unless you mean imbalance. In many cases and we have seen lots of them, one just keeps failing when trying to bring levels back up. It has to do with solution kinetics and with something like Marine Buffer it is mess. This, what Lynn has, is not the first time it has come up, it is all over our Chem forum on RC to the point where both Randy and Craig have written about. Randy himself will tell you that if you keep trying to raise the Ca++ and fail, if the Mg++ is normal, despite the Alk to do water changes. At her pH and Alk adding Ca++ to 400 will do nothing for the Alk. It will need to be much higher that 400 and the pH needs to be higher.


Lynn

Although not asked yet, Lynn what are your Mg++ levels. Buffers like Marine Buffer or lows Mg++ will suppress the Ca++ more than anything. Reason, the Mg++ stops the Ca++ from leaving solution. Meaning, when it is low the abiotic precip increases. It is possibe that this is the issue but I doubt it.

 

[lcstorc]

Mag was 1300 when tested Monday night.

 

[JWarren]

"Yes I know and when I said "we" do not recommend this that means me and Randy."

Then Randy should get his name off that article.
I'll send an e-mail off to him about it.

"They method of using CaCl2 or buffer to fix"

I never said anything about any buffers Boomer, just CaCl2 and I must say it did work and yes there was some precipitation but it was no snow storm by any means. Once I was able to get back in balance I continued dosing Kalk and the pH rose back up. Buffers is what got me in my mess as well, so I know for sure I would never recommend adding any buffers to aid this type of situation.

 

[Boomer]

I must say it did work

Yes John it does work at times but as you stated so I know for sure I would never recommend adding any buffers to aid this type of situation. it is not good idea


I never said anything about any buffers Boomer, just CaCl2

I know but the other method to lower the Ca++, if high, is to add buffers.

Often the case is the Alk is not high enough to get the alk down unless the Ca++ is very high is my point. 4.5 is not all that high and using Marine Buffer as I stated the CO3--end will not being 4.5 meq due to the high Borate but much less like ~ 3.5 meq /l maybe. The low pH will suppress this from happening even more. Abiotic is a function of temp, Ca++, Mg++ Alk , pH and they have to match up to a point. Lynn has been adding Ca++ and it is not helping much. I don't want her dumping in a bunch of CaCl2 and having a snowstorm or the issue is still the same. The other issue is that with snow storms or any Abiotic falling out and into the water column or like Purple -Up which is the same thing, the fines of calcite/aragonite end up in you Alk test kit sample and skews the Alk even more, as the acid in the test kit will dissolve them giving high false readings.

"I'll send an e-mail off to him about it."

It will never happen he has them all closed same for PM's. Reason, waaaaaaaaaaaayyyyyyyyyy to many people PM and e-mailed him and he final decided that was enough. It was me that told him to close things up. How would you like 50 PM's / day

Then Randy should get his name off that article.


Well he will tell you that lots of those articles would have changes if he was to re-do them

 

[Boomer]

Then Lynn I would suggest water changes, as they seem to fix things.

 

[lcstorc]

Water changes and aeration. Don't add any supplements. Is that right?
Any suggestions on salt or salts to avoid. I was using Oceanic but apparently that is exactly the opposite of what I want to do.
Thanks

 

[Boomer]

We need to find out first if you have high room air CO2. Turn off the air for one night and open the window to see if the tank pH goes up. Only 3 things cause low pH, high room air CO2, to much uneaten food, aka dirty tank pulling it down or a Calcium reactor. Try Reef Crystals, check the Alk, pH, Mg++ and Ca++ after it is mixed. If low in any of them then bring them up tp par, i.e., pH 8.3, Alk 3.5 or so, Ca++ 400 -450 and Mg++ ~ 1300 or so, them change the water with it after the RC is fixed.

 

[JWarren]

I know but the other method to lower the Ca++, if high, is to add buffers.

I would never recommend this to anyone at all.

Lynn, theres always Instant Ocean, which I have used as the only salt I will use. Even though there is one I am keeping my eye on, but I have no experience with it yet, so I don't recommend it.

 

[lcstorc]

Hmm the uneaten food is one not mentioned before. That is more likely than the CO2 changing. Regardless we will try the air check and see what results that brings. Would I see results in a couple of hours on the aeration? If so I can have Frank add the fans to the windows tonight when he gets home from work. It is easy enough to check the ph after a couple of hours. I may even be able to talk him into checking in the morning after leaving it open overnight.

 

[Woodstock]

I am guessing the low ph is from the high co2 rusulting from one or more of the following: high indoor co2, aged deep bed crushed coral substrate, heavy bioload and heavy feedings.

 

[lcstorc]

hmm I have crushed coral as well though not very deep. It has been there about 3 years though.
We'll try the window/fans thing tonight and see what that does.
Then when I do a water change I will be sure to stir up the CC and vacuum out anything I can find. I'll go ahead and clean out the sump as well in case there is uneaten food or anything in there.
I would think if it is overfeeding or overstocking I would see some nitrates or phosphates or something but the major vacuuming is a good idea regardless. I do some vacuuming during a regular water change but I will get serious about it this time.
We'll see what happens. Hopefully that will get things at least headed in the right direction.

 

[BobBursek]

Not to Hijack,
but Boomer how is your PH this winter in Up North? How do you deal with the CO2 issue in your house? I have the CO2 PH problem here too, and thanks for the PM last night.
Thanks!