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bklynmet
10-30-2006, 11:02 PM
Just got pH probe hooked up this past Friday and its been calibrated with 7.0 and 10 solutions. The probe is part of the AC Jr. Anyway, its great getting constant reading. Now, Ive know my pH tends to be on the low side but the monitoring is giving me the following - 8.15 during lights on and 7.85 with lights off. dkH is 10. Mg is low at 1200 ppm and I am slowly bringing that up with mag flakes. Ca was measured at 460ppm. I use kalk water for topoff. I use two-part solution for when Ca and Alk dip lower - but it's rare since starting the kalk two months ago.

My question is how concerned should I be about the pH. I know a pH swing is eveitable after lights out.. I have a refugium lit on a reverse cycle. The skimer is on 24/7. Windows are closed now that it's cooler outside and we have the heat on.
I do not know what else I can do to raise it - but the livestock - corals and fish seem unaffected - except for an anchor hammer who has its polyps not fully extended. Im not sure if it is pH ralated or the sixline bothering it.

what do you think?

Boomer
10-31-2006, 12:40 AM
Stop the two-part, increase the kalk in the top-off and drip it at night only. This will be trial and error to get it where you want it. Watch the Alk, it is Ok to get up to 11, no higher. Watch the Ca++, it is already getting to high. Increase surface turbulence if you can to drive off CO2. Your low pH is due to increased CO2 at night. You pH swing to to large it is .3 pH units. Try to get it half of that or a .1 - .15 unit swing.

NaH2O
10-31-2006, 10:46 AM
Boomer, when you say "increase the kalk in the top off" what do you mean by that? Add more kalk? I have a similar problem with my pH right now (and always do this time of year) where I am 7.97 at night and 8.15 or so at the end of my photoperiod. My kalk is dosed through my top-off in a kalk reactor. I have even run my skimmer's airline out the window (we have all gas appliances). I have as much surface aggitation as I can have without splashing water (coast to coast overflow and return via sea swirl makes ripples across the surface). Currently, my alk is a little on the low side, which I'm in the process of correcting, but even when my parameters are balanced my pH is like this. Maybe I should not talk so much on the phone ;), or I need to hold my breath, or a good excuse not to make dinner? I'm going to be recalibrating my pH probe, but it has been pretty accurate with past calibrations. I need to look into getting a Calcium reactor soon, but I'm not wanting to go there because I don't want the pH dropping any lower than it already is.

I guess I'll be tagging along with this thread...

DonW
10-31-2006, 12:09 PM
I'll throw in another question. Is there a difference in how well different buffers work. I used to have all sorts of ph issues and like magic they went away the same month I installed my current calcium reactor. The only thing changed was I stopped using kalk. We know it wasnt magic, so what happened?

Don

Boomer
10-31-2006, 01:27 PM
Nikki

Some do not use a saturated solution of kalk, which is 2 tsp / gal. Same question for you do you run the kalk only at night or 24/7. A kalk reactor is thw way to go usually for pH issues.

pH probe calibration ? Who's calibration solutiuon are you using ? Some are way off. Meaning, you coluld be 8.15 night and 8.3 day. I would not worry much about a .15 pH swing that is fine. Part of your low pH is due to your low Alk.

A Comparison of pH Calibration Buffers
http://reefkeeping.com/issues/2005-02/rhf/index.htm

Don

Yes there is a difference. It based on the ratio and types of various buffers that make up the buffer. For example, using straight baking soda will incresae the Alk but may have little effect on the pH. Washing soda by itself will drive them both up. Some are a combination of the two. Some may have other salts like borate. In NSW borate makes up about .15 meq/ l Alk. There are some very expenisve buffers that if you put a fish in a bag and ship him half-way around the world the pH in the bag does not change, even though the fish is pushing out all kinds of CO2 which should kill the pH.

Are you using a dual reactor Don ?

This part only thing changed was I stopped using kalk. I'm not sure here if the two were maybe mixing some how or not. Many that use reactors have to use kalk to keep the pH from falling. The extra OH- form the kalk will help both the pH and Alk. The other thing reactors or kalk is you anre not adding things like sodium, potaasium which are in some buffers


This may help

Hydroxide Addition
For hydroxide addition, the first thing that happens is that bicarbonate is converted into carbonate:
9. HCO3- + OH- ==> CO3--

and the small amount of carbonic acid present is converted into bicarbonate:
10. H2CO3 + OH- ==> HCO3- + H2O

The net effect is that the pH rise that is normally encountered by adding hydroxide to water is reduced. For example, adding 0.5 meq/L of hydroxide to freshwater would drive the pH into the 10’s. In seawater, the pH rises much less, and the conversion of bicarbonate to carbonate is largely responsible.

In this situation, the tank is now deficient in H2CO3 (because the small equilibrium amount of H2CO3 normally present was partially converted to bicarbonate by the OH- addition), and the tank proceeds to absorb CO2 from the air, bringing the pH back down a bit by releasing H+. There are many ways to show these reactions, but the net process involves CO2 from the air becoming carbonic acid, the carbonic acid deprotonating to bicarbonate, and some of the bicarbonate deprotonating to carbonate:

11. CO2 (atmosphere) + H2O ==> H2CO3
12. H2CO3 ==>HCO3- + H+
13. HCO3- ==> CO3-- + H+

Carbonate Addition
The case for carbonate addition is similar to that for hydroxide. In this situation, the pH rises because much of the carbonate combines with H+ to form bicarbonate. This obviously reduces the H+, which results in a higher pH:

14. H+ + CO3-- (added) ==> HCO3-
In this case, the net short-term effect is that carbonate and bicarbonate increase, and the pH rises (from 8.10 to 8.44 in the experiment above). In the long term, the higher pH causes more CO2 to be pulled in from the air, as was the case with hydroxide additions. This limits the pH rise, and further increases the bicarbonate concentration. Still, the end effect is the same as hydroxide addition: the tank experiences an increase in bicarbonate and carbonate, and in pH

Bicarbonate Addition
The addition of bicarbonate as an alkalinity supplement is rather different. In this case, the bicarbonate partially dissociates into carbonate and H+, and the tank experiences an increase in bicarbonate and carbonate, and a drop in pH.:

15. HCO3- ==> H+ + CO3--
Consequently, the immediate effect on pH is for it to drop. The drop is small because not much of the bicarbonate dissociates at normal tank pH, but enough does to drive the pH a bit lower (from 8.10 to 8.06 in the experiment above).
In the long term, however, the effect is different. Since a substantial amount of bicarbonate was added and the pH did not change much, the tank is now overloaded with bicarbonate with respect to what it would normally have in equilibrium with air. Some of the bicarbonate picks up a proton, becomes carbonic acid, and the pH rises as the CO2 is blown off to the atmosphere:

16. HCO3- + H+ ==> H2CO3 ==> CO2 + H2O

In the experiment above, this effect has caused the pH to rise from 8.06 to 8.33. So the long-term effect of bicarbonate addition (as it is for any addition to carbonate alkalinity) is to raise pH even though the short-term effect was to lower it.

For more http://www.advancedaquarist.com/issues/may2002/chem.htm

Something else for you Donny :D

Your K+ thing

It just it me :D

Why not just use some buffer for K+ additions like potassium bicarbonate or potassium carbonate, if one feels a need to add K+ ? These were never brought up IIRC. SeaChem Labs "Marine Buffer" has such, not that one should use this.

DonW
10-31-2006, 02:24 PM
Boomer
No just a single little schuran reactor. I stopped using kalk at the same time I installed the reactor. It seems almost as if the natural media is doing a better job at buffering ph than the soda and kalk ever did.
As far as the k thing goes. I'm dosing 2ml hr of 4tsp K bicarb in 1000ml water. Thats what it takes to keep it right at 380 any less it falls.

Don

NaH2O
10-31-2006, 03:26 PM
The kalk is being dosed 24/7 via my auto-top off (if it matters, I'm using Warner Marine's Kalk Plus). There is usually only between 5-10 gallons of RO/DI water in my top-off resevoir at any given time (to avoid a potential disaster, as Nikki's Law would guarantee a disaster if I didn't manually fill the resevoir). I do wonder what the difference would be if dosed only at night. I suppose I didn't think that my evaporation would be lower also at night, when my lights and fans are off, so there probably isn't much topping off taking place. However, I'm leary of only having my top-off on after lights out. It would be dosed too quickly? I use the Tunze Osmolator as my auto top-off.

As for calibration solution, I use the Pinpoint brand on my AquaController.

Don, are you using the Schuran media with your reactor?

I still need to go back and read the bold in the reply to Don. Kind of hard to wrap my brain around it with a 5 year old hyped up about going Trick-or-Treating.

Slickdonkey
10-31-2006, 05:05 PM
Ok a lot of this is over my head but thought I'd point out you should be sure that your Aquacontroller is reading the correct pH. I and others have been having problems with the lab-grade probe reading up to 0.25 units less than a similarly calibrated Pinpoint monitor.

http://www.reefcentral.com/forums/showthread.php?s=&threadid=956861

I once read one of Randy's articles and he said the most common cause of pH problems is a measurement problem.

I have been struggling with my pH; it has been fluctuating between 7.8 and 8.0, which seems a little low to me. However, I'm beginning to believe this is a problem with my Aquacontroller pH probe rather than an actual problem with my tank.

DonW
10-31-2006, 05:49 PM
Don, are you using the Schuran media with your reactor?


Yes, well sort of. I use Schuran style media. Pretty much what ever I can find at the time I order it. There is Schuran and there are a few copy cat brands.

Don

Boomer
10-31-2006, 06:01 PM
Don

Ok then that is great for you. Who cares as to why :lol:

On K +

I did not remember if K+ bicarb was brought out. It is not on our RC chem forum, a least I could not find it. It was all K+ chloride . You made me think about this when you asked are buffers different as some buffers use these.

Nikki

Those cal solutions by PinPoint are right on if you look at the article.

Same question again, is your kalk mix sat. @ 2 tsp / gal ?

DonW
10-31-2006, 07:18 PM
Don

Ok then that is great for you. Who cares as to why :lol:

On K +

I did not remember if K+ bicarb was brought out. It is not on our RC chem forum, a least I could not find it. It was all K+ chloride . You made me think about this when you asked are buffers different as some buffers use these.

Nikki

Those cal solutions by PinPoint are right on if you look at the article.

Same question again, is your kalk mix sat. @ 2 tsp / gal ?

Yes we talked about it since I cant get K+ chloride. The state of WA is afraid we might go aroung giving people leathal injections.:)

Don

bklynmet
10-31-2006, 10:47 PM
Boomer - you are correct in that I am only using 1 tsp per gallon. I'll up it to two and get it to topoff only at night. I hope the water fluctuation doesn't affect the skimmer performace in the sump.

Surface is agitated during the day - with the closed loop on. At night, its not so much so I'll attemp that as well by directing the return water a little higher. I'll also stop the two part and keep an eye on alk.

The probe was calibrated with pinpoint 7 and pinpont 10 - both recommended in the article linked above.

NaH2O
11-01-2006, 07:40 AM
Yes, well sort of. I use Schuran style media. Pretty much what ever I can find at the time I order it. There is Schuran and there are a few copy cat brands.

Don

Thanks, Don. I was just curious more than anything. There are a number of local reefers that are using Gen-X media that reminds me of the Schuran.



Nikki

Those cal solutions by PinPoint are right on if you look at the article.

Same question again, is your kalk mix sat. @ 2 tsp / gal ?

Well, I suppose I am. How's that for an answer :D? I evaporate about 2 gallons a day, so I put in 20 tsp of kalk into the reactor and add more in about 10 days. Should I be testing the pH of the kalk reactor? Maybe I'm not using the reactor correctly. I should start paying more attention to how much water I am evaporating, too. I wonder if my top-off amount has changed.

DonW
11-01-2006, 10:24 AM
Thanks, Don. I was just curious more than anything. There are a number of local reefers that are using Gen-X media that reminds me of the Schuran.



Well, I suppose I am. How's that for an answer :D? I evaporate about 2 gallons a day, so I put in 20 tsp of kalk into the reactor and add more in about 10 days. Should I be testing the pH of the kalk reactor? Maybe I'm not using the reactor correctly. I should start paying more attention to how much water I am evaporating, too. I wonder if my top-off amount has changed.


Nikki,
You can run your reactor only at night with your ato. You need a bypass valve on the pump. If you down load the pdf instructions for the deltec kalk reactors there is a pretty good explanation of how to do this. This way your not just doing a full two gallon top off and spiking your ph.

Don

NaH2O
11-01-2006, 11:28 AM
Thanks, Don. I'll download those instructions, and see if I can find a bypass valve. The only thing is if I'm not evaporating that much at night, then I'll hardly have any kalk dosing at all because the top-off won't be running as much. Does that make sense?

DonW
11-01-2006, 11:40 AM
Thanks, Don. I'll download those instructions, and see if I can find a bypass valve. The only thing is if I'm not evaporating that much at night, then I'll hardly have any kalk dosing at all because the top-off won't be running as much. Does that make sense?

I get what your thinking. You use a timer so your only topping off at night.:)

Don

Boomer
11-01-2006, 12:16 PM
Nikki that pH for sat kalk solution should be at or near 12.5, @ 77F. Near reef temps of 82F it will be a tad less, like 12.3. No, that is not a typo:D. Kalk is one of those odd duck chemcials where there is more in solution at lower temps, thus a higher pH at lower temps. and a lower pH at higher temps.

You should be able to find a time line. Even if it is 2 hrs before lights out and 2 hrs after lights on.

bklynmet
11-01-2006, 01:40 PM
Thanks, Don. I'll download those instructions, and see if I can find a bypass valve. The only thing is if I'm not evaporating that much at night, then I'll hardly have any kalk dosing at all because the top-off won't be running as much. Does that make sense?

I adjusted my topoff pump to be on only during nightime hours with my AC Jr last night though a timer will work fine just as well. I get about 1.25 gals evap a day when not in summer and about 2.25 during summer.
I'm concerned about the side effect of skimmer performance being affected since the water level in sump would drop through the day until top-off starts at night. I guess I can have the skimmer in a container with it's output set above the waterline so influences of in-sump water levels are not a factor (per one of Calfo's discussions) - it just adds an additional item in an already clutterd sump.

Boomer, I did notice pH 0.05 higher after adjusting the return pump to agitate the surface. Thanks for that simple suggestion. I have a DIY kalk reactor that I need to put online once I get a pump for it. That would put saturated kalk into the system.
Question - I guess then I'd have to topoff separate from kalk because I wouldn't want too much saturated kalk in the system - correct? Is there an easy way to automate this without getting a separate dosing pump or manually setting opening/closing bypass valves?

DonW
11-01-2006, 02:30 PM
You want to be careful how you go about using a ato with kalk only at night. If you let the sump go low all day long , when the timer turns on the ato is going to want to fill it back up until the float shuts it off. You want to make sure that its a slow drip process thus the need for a bypass valve if your using a pump for the ato. A bypass valve is nothing more than a t connection and a jg type valve diverting the water back to the ato tank.

Don

Boomer
11-01-2006, 03:59 PM
As Don has stated you need to be careful. It is all trial and error. Yes you could to-off seperate. I would look to Don for better answers here :)

And no you do not want to add to much sat kalk, but some use it full strength. It depends on the demand and the evap rate. The easy way is once you get things set up on time vs evap rate, day and night and how that seems to fit in, then start Kalk at say 1 tsp /gal and see what readings you get. Then bump-up the kalk to the next level, guessing maybe 1 1/2 tsp will do it, then the next level. Going beyound 2 tsps / gal will do nothng but cause precip.

Kepp an eye on tank pH, Alk and check the effleunt pH of the kalk reactor. What is the pH of the kalk solution you are using now ?

bklynmet
11-01-2006, 06:38 PM
Boomer,

pH if water in the kalk resevoir is 11.5. Note that I just upped the dosage from 1 to 2 tsp last night so about 1/4 to 1/3 of the resevoir is at the new dosage.

I'll look into the bypass and seeing how that is plumbed. Thanks.

Boomer
11-01-2006, 08:11 PM
OK, recheck it later to see what it is. If still at 11.5 it can still go 1 pH unit higher almost. Shoot for just over 12 to be safe.

bklynmet
11-01-2006, 08:28 PM
DonW. You make a good point.
I now see what you mean my the bypass - I looked at Deltec's PDF instructions.

I don't have that issue because I topoff with a peristalic pump and have it running for no more than one minute at at time which equates to 1.65 ounces max each time it kicks on. I adjust the time gap between time it kicks on - never to fill up more than evaporation in a day. (Gotta love the Aquacontroller:)) A float switch set a little higher up is there for backup.

bklynmet
11-05-2006, 12:33 PM
Boomer.. after getting things setup, things were working great for two days.. the pH was at 8.05 day and 8.01 at night... extremely stable though not the target minimum of 8.1. Alk was at 11dkH. Calc was at 430 and Mg being raised from 1200 and not measured then. New growth of coralline and monti cap was evident and great. dosing the kalk at night was working great.

But, this morning I got up, and the pH was at 7.84 and the Alk at 9dkH... Mg is now at 1300. The top-off w/ kalk did work overnight... measured Calc at 400ppm and Mg is now at 1300 (all salifert). check the probe against a calibrated solution and it was on target. pH of kalk solution was 12.

Does the drop in pH, Alk and calc mean I need to start up the 2 part again?
Nothing was done to the tank the past week (aside from starting the top-off only at night) except on thurday evening I did a 10% water change and cleaned out the siphon over flow which had a ton of hair algae and stuff in it...

do you think the algae in there was producing oxygen to raise the pH during the day and the removal of it is now creating a oxygen deficiency? or do I need to start the two part regiment up again.

DonW
11-05-2006, 12:41 PM
The 10% water change may have be your culprit if your using IO and not adjusting the fresh mix.

Don

bklynmet
11-05-2006, 01:03 PM
The 10% water change may have be your culprit if your using IO and not adjusting the fresh mix.

Don

Don, you lost me.. IO?

I use RO/DI water and premix the fresh mix at least 24 hours prior (actually it's constantly being aerated in a resevoir at a SG equal to the tank.). I should test the water in there and see where that's at for pH, ALk and Ca and see if that is that is the cause.

DonW
11-05-2006, 01:30 PM
Don, you lost me.. IO?

I use RO/DI water and premix the fresh mix at least 24 hours prior (actually it's constantly being aerated in a resevoir at a SG equal to the tank.). I should test the water in there and see where that's at for pH, ALk and Ca and see if that is that is the cause.

IO is Intant Ocean salt. Yes you should be checking and adjusting your salt mix. IO usually comes in around 380 so if you do a water change your going to lower your ca mg and alk if you want your alk over 9.

Don

bklynmet
11-05-2006, 02:37 PM
Oh.. but I use Coralife Salt mix.

Boomer
11-05-2006, 10:31 PM
do you think the algae in there was producing oxygen to raise the pH during the day and the removal of it is now creating a oxygen deficiency

Oxygen has no effect on pH. It is CO2. As CO2 is removed during the day the pH goes up and as CO2 increases during the night, due to plants resting and giving off CO2, it then goes down..

It still may have been the salt mix as Don suggested, that is the only logical explanation. How did you mix that salt? Did you add the salt to water or water to salt. How long did it sit under aeration before you used it ?

bklynmet
11-06-2006, 09:04 AM
update: ph is up to 7.98 this morning - before lights on....

husbandy: I have a resevoir receiving fresh RO/DI. The water is constantly mixed via pump. I add salt to water to get to proper salinity the day before a water change. Let it mix with the water being agitated by the pump. After 24 hours re-check sailinity, check temp, then transport waterneeded to tank. There is usally a few gallons left in the resevoir. Resevoir gets cleaned every six months. Last resevoir cleaving was 1.5 months ago. Water changes are weekly.

So the pH is driven up during the day solely by the photosytheic organisms stopping the production of carbon dioxide (because they're producing oxygen) and the increased circulation of the pumps turning on during the day that drive off CO2. Correct?

Do I need to start a 2-part regiment again to replenish calcium and alk based on the post above from 11-05-2006 12:33 PM?

DonW
11-06-2006, 10:13 AM
and the increased circulation of the pumps turning on during the day that drive off CO2. Correct?



Are you turning pumps off at night? Still may be a salt issue, test the fresh mix.

Don

Boomer
11-06-2006, 12:02 PM
What is the pH now during the day ? 7.98 is not something I would worry about vbefore light on but yes it would be nicer to see it higher than 8. What is the kalk mix pH ? You should get it just above 12 before we try or play with other things.

So the pH is driven up during the day solely by the photosytheic organisms stopping the production of carbon dioxide (because they're producing oxygen) and the increased circulation of the pumps turning on during the day that drive off CO2. Correct?

Yes more or less but high room air CO2 can also keep the pH down which may be your issue. Open a couple of windows if you can for a 2-3 hrs and see if the pH goes up.

Do I need to start a 2-part regiment again to replenish calcium and alk based on the post above from 11-05-2006 12:33 PM?

Not yet, we need to see what the damand is, ie. how much the Alk and Ca++ drop each day with the kalk use if it does. Right now your Alk, Ca++ and Mg++ are perfect. It is just a slight pH issue.

bklynmet
11-06-2006, 09:06 PM
I think I'm going to prolong the photo period so it's on for for 12 hours from the time the first lights come on instead of the current total of 10. That should probably help as well. Same with the closed loop - increasing the time those pumps stay on for an additional 2 hours. I'm going to be replacing the CL with two modded MJ1200s as soon as I make a bracket for them.

I don't know how familiar you are with Lifereef Skimmers but they are venturi that doesn't draw fresh air but draw air from the collection cup. This keeps the venturi moist and salt creep is non existant. So my skimmer may be handicapping things just a little due to this feature.

opening windows isnt an option because the wife and kids are home during the day and it's cool outside.

pH of kalk is still 11.5.. I dont know if the max the controller can read is that or not or just the max that Mrs Wages can reach. I tested a freshly mixed solution and it was 11.5. Also rechecked against calibrated solutions and they were on target at 7 and 10.. I'll ask Curt from Neptune about it.



I'm going to log the ph on the graph below over a weeks time to see what happens.
http://www.reeffrontiers.com/photos_members/showphoto.php?photo=5636

Boomer
11-06-2006, 09:31 PM
bkly

Was that at 2 tsps / gal and it was still 11.5 ? If it is not in the low 12's it is not saturated.

Some things to look at.

Limewater (kalkwasser)

What Your Grandmother Never Told You About Lime
http://reefkeeping.com/issues/2005-01/rhf/index.htm

The Self Purification of Limewater (Kalkwasser)
http://www.advancedaquarist.com/issues/may2003/chem.htm

The Degradation of Limewater (Kalkwasser) in Air
http://reefkeeping.com/issues/2003-...ature/index.htm

Magnesium and Strontium in Limewater
http://www.advancedaquarist.com/issues/dec2003/chem.htm




I know Jeff Turcheck form LifeReefs very well but have not taked to him in ages :(

bklynmet
11-06-2006, 10:14 PM
bkly

Was that at 2 tsps / gal and it was still 11.5 ? If it is not in the low 12's it is not saturated.



yep .. 2tsp/gal of mrs wages... thats why I emailed Curt at Neptune to see if it's an equipment thing. (However, as stated the contorller was reading the calibration solution on target). The limewater/kalk is in a sealed container penetrated only by the airline tubing feeding the pump and very tiny airhole. Also, the limewater in the resevoir gets used up within a week so it doesn't get a chance to substantially degrade per the articles studies - I think anyway.


I ask myself what I'd be doing right now without the constant pH readout.. I'd sleep easier. But one good thing I've noticed is increased stability in the pH swings and a burst of growth when things got stable (ang I got Mg to 1300).

This thread has been good in that the intial suggestions of solely topping off at night and redirecting the return to agitate the surface more helped withthe daily pH swings tremendously. Also, diatoms/algae has been slower in growing on the glass too! So, I thank you Boomer and Don for that.

I keep telling myself that there no magic pill and that with patience we'll get things situated and balanced in the tank. I'll keep you posted on what Curt tells me about the AC Jr and pH. Once I get the resevoir ready with new saltwater for the next water change, I'll post the make-up water parameters as well and see if that is the culprit. Thanks again.:D

pfish
11-07-2006, 12:47 AM
Excellent info in this tread.

pfish
11-07-2006, 12:47 AM
thread, lol.

Boomer
11-07-2006, 07:27 PM
You are welcome from me and Don :D


Try adding more Mrs Wages next time and see if the pH will go into the 12's

bklynmet
11-07-2006, 08:11 PM
phfish.. thanks... boomer and DonW have really been helpfull.

Boomer - I did that yesterday just in a liter bottle adding 3 tsp (just to be sure there was enough kalk in there) and had the same result.. but wait - I now know why my AC Jr reads 11.5. I got an answer from Curt at Neptune - read by clicking here (http://reefcentral.com/forums/showthread.php?s=&threadid=967079)

So the issue w.r.t. measurement of kalk's pH. My particular AC JR is not inaccurate - just cannot measure anything higher than pH of 11.5. Judging on how quick the pH shoots up and stops all of a sudden at 11.5, I believe the kalk is saturated at above 12.

Today's update - I lengthened the light's photoperiod -ON for two additional hours - so it's on 12 hours of photoperiod (10 with all six lamps lit). pH was higher this morning at 6AM than yesterday at 6 AM. see the graph comparing the days here:
http://www.reeffrontiers.com/photos_members/showphoto.php?photo=5640&cat=500&ppuser=14233

bklynmet
11-12-2006, 02:23 PM
ok. update. I 'tested my air' by basically doing Randy Holmes Farley's recommendation of filling a cup and aerating with fresh air and inside air for one hour respectively and comparing the pH. The inside air resulted in a pH 0.15 lower than the fresh air - meaning the inside air has more CO2 - and the reason I cannot drive it up higher. It also explains why the pH dips a tad during the day - increased ciruculation aerates the tank with CO2 air.

Also I got to testing the makeup water for water changes, the pH in the makeup water was a little lower than that of the tank - because it was being aerated with in-house air as well.

Source of CO2 - well in addition to us breathing the furnace is in the next room creates CO2 as it burns the natural gas. My plan - bring airline from the garage to supply the tank with fresh air. It's the least obtrusive plan I can think of so far unless there is another idea.

Boomer
11-13-2006, 12:03 AM
All sounds good bkly

NaH2O
12-06-2006, 11:22 AM
bklynmet - did you try running an outside air to the tank yet? Just curious if it made a difference.

DonW
12-06-2006, 11:54 AM
bklynmet - did you try running an outside air to the tank yet? Just curious if it made a difference.

Ive been fighting co2 issues for the past few years, nothing worked. The airline for the skimmer did nothing to help. I just added a 1/2 barb fitting to my drain pipe and connected a BIG airpump that sits outside. It runs only at night but has worked great. PH swing is now gone. I may code it into the controller, if I run it 24/7 the PH will climb to high during the day.

Don

pfish
12-06-2006, 12:13 PM
Don : Thats very interesting, could you explain what type of air pump and which drain you conected it to? I assume you meen the skimmer drain?
Thanks.

DonW
12-06-2006, 12:31 PM
Don : Thats very interesting, could you explain what type of air pump and which drain you conected it to? I assume you meen the skimmer drain?
Thanks.

I'm using a outdoor Whitewater TL40 rated at 1.8cfm plumbed into the 1.5"overflow drain crossover pipe. I installed a barb and elbow so the air flows the direction of the water to eliminate noise.

Don

Boomer
12-06-2006, 12:38 PM
Another great idea from you Don :D

DonW
12-06-2006, 01:12 PM
Another great idea from you Don :D

Thanks, sure beats the kalkwasser. One thing I'd have to warn folks about is temp. Its not very cold here and this much air will drive temp down, so you need to make sure the heating system is working well.

Don

Slickdonkey
12-06-2006, 01:26 PM
Hey, that's a good idea. So you tee off the drain to your sump, put a barb fitting, and just blast air in there?

DonW
12-06-2006, 01:33 PM
Hey, that's a good idea. So you tee off the drain to your sump, put a barb fitting, and just blast air in there?

Yup pretty much all there is to it. I would suggest a elbow inside the pipe directing the flow with the direction of the water. Otherwise with a pump this size there is ALOT of noise, the elbow makes it silent. Dont forget a check valve you dont want wter in the pump if its lower than the drain pipe. These are not just cheap little aquarium pumps they push alot of air and can handle alot of depth.

Don

Slickdonkey
12-06-2006, 01:36 PM
I would suggest a elbow inside the pipe directing the flow with the direction of the water. Otherwise with a pump this size there is ALOT of noise, the elbow makes it silent.

I'm having trouble picturing this in my head...?

DonW
12-06-2006, 01:59 PM
I'm having trouble picturing this in my head...?

Cut a hole big enough for a 3/4 unseal. Stuff a 1/2 pvc elbow in the uniseal so that only a little stub is sticking out. Attatch the hose to that stub.

Make more sense?

Don

pfish
12-08-2006, 02:47 AM
Sorry I don't know what a uniseal is ? this sounds like the solution to my problems. Can you post some pictures of this set up?
Thanks

Boomer
12-08-2006, 09:53 AM
This is what Don means

http://www.tank-depot.com/productimages/uniseal180.jpg

DonW
12-08-2006, 10:55 AM
Thanks Boomer. Pfish, If your going to do this, just make sure you get that elbow in there. Although it cures the noise issues it also keeps the air from erroding the drain pipe.

Don

bmtpfgh
12-08-2006, 10:58 AM
Thanks for the pic,Boomer.
So,you use a 3/4" Uniseal with 1/2" pipe?

DonW
12-08-2006, 11:13 AM
Thanks for the pic,Boomer.
So,you use a 3/4" Uniseal with 1/2" pipe?

Ya because a 1/2" pvc female slip elbow is 3/4 od. Really what ever you want will work. It just needs to be 1/2 for the pump I use and they just bigger from there.

Don

bmtpfgh
12-08-2006, 11:55 AM
Thanks for the clarification,Don.I had just ordered some Uniseals for another project,and was a little worried I had ordered the wrong sizes!

Slickdonkey
12-08-2006, 01:06 PM
Don, what about just pumping the air into the sump with some vinyl tubing from the air pump? My sump is under the house so I don't think noise would be a big issue.

DonW
12-08-2006, 01:45 PM
Don, what about just pumping the air into the sump with some vinyl tubing from the air pump? My sump is under the house so I don't think noise would be a big issue.

We are talking alot of air, these are not little aquarium pumps probably going to make a mess. I would also think the effect would be different due to surface area.

Don

pfish
12-09-2006, 02:25 AM
Don: What if you pumped into the skimmer air intake? I have a hose pumped into the skimmer air intake from outside the house which is fed with a computer fan. I have noticed less pH swing put still not optimal. I think maybe The air pump you are using may do the trick.
What do you think?

DonW
12-09-2006, 01:14 PM
Don: What if you pumped into the skimmer air intake? I have a hose pumped into the skimmer air intake from outside the house which is fed with a computer fan. I have noticed less pH swing put still not optimal. I think maybe The air pump you are using may do the trick.
What do you think?

With a pump of this size either the skimmer would stop pumping or may explode.:lol:

Don

pfish
12-10-2006, 01:36 AM
Got ya : Thanks Don