alkalinity problem

[cheeks69]

I'm wondering what could cause in increase in alk without doing any W/C's adding any supplements or kalk ?

alk 14dkh
cal 400
mag 1200
ph 8.5

[Tarasco]

That's a tough one. Were there any environmental changes around the tank, or anything that would have an effect? I don't think that would matter anyways, just a guess. You're ph is kinda high too. Carbon dioxide won't have an effect would it? Chemistry isn't my thing...

[Maxx]

Nah, Co2 would lower the pH, not raise it...
I dunno...lemme PM Boomer...super Chem genius that he is.

Nick

[Travis]

http://www.reefsanctuary.com/knowled...links.php?c=14

[Boomer]

I'm wondering what could cause in increase in alk without doing any W/C's adding any supplements or kalk ?

If that is actually happening, the test kits are correct, then something in the tank is going into solution. It appears so, as the pH is also high.

[Brucey]

Hi cheeks. OK, I'm no chemistry expert and boomer really is your man . . . . but an obvious anser comes to mind for me but we would need to know a range of test values over a given period of time . . . . Alk is linked to Calcium as we all know. Balancing the two is like trying to juggle three water mellons . . . . but if something in your tank is eating up your calcium levels so they have dropped over a period of time, doesn't it follow that the alk will go up as the ca comes down. Boomer will prob tell me I'm talking out of my a#$e but that's what I immediatley thought
Brucey

[Woodstock]

Aragonite disolving would do that... do you have a DSB? You are sorta in the middle of #1 and #3....

http://www.advancedaquarist.com/issues/nov2002/chem.htm

Corrections for Zone 1

Zone 1 is the easiest problem to correct. Unfortunately, it is also very uncommon. In this case, both calcium and alkalinity are on the high side of normal. Moreover, if you leave the tank alone, the problem will likely correct itself, and you will end up in the red target zone (though you may also pass through it into zone 2 if you wait too long).

What this zone implies is that both calcium and alkalinity are elevated, and that by removing calcium carbonate from the water, either through biotic deposition into coral skeletons or coralline algae, or through abiotic precipitation, as on heaters, the levels of each will drop in an appropriate ratio. More specifically, the tank parameters will move along a line parallel to the two lines bordering this zone, and directly into the red target zone (the blue arrow in Figure 2). If you are smack in the middle between these two lines, as in Figure 2, then you will continue to move in the middle of these two lines down into the target zone.


This movement can continue right out the bottom end of the target zone (into zone 2), of course, so once you reach the target zone, you’ll have to reinitiate normal calcium and alkalinity additions.

[Woodstock]

http://www.advancedaquarist.com/issues/nov2002/chem.htm

Corrections for Zone 3

Zone 3 problems are a little harder to correct, and are fairly common. It is, in fact, the problem in the real question posed at the beginning of this article (it doesn’t say so there, but the alkalinity was 3.2 meq/L). This problem is typically caused by overdosing alkalinity RELATIVE to calcium, but does not necessarily imply that calcium is either too high or too low (though it is almost always too low). To correct problems in this zone, monitoring of calcium and alkalinity values during correction is especially important.

One more word about this zone before getting to solutions: Many tanks end up here because aquarists are trying to correct pH problems by adding “buffer.” In my opinion, one should not try to correct any pH problem by simply adding an alkalinity supplement. If you are low on alkalinity, it is a fine course of action to raise the alkalinity. But if alkalinity is OK, or even high, adding an alkalinity supplement to alter the pH may simply create a worse problem. Better solutions to pH problems are discussed in this recent article6.

If this problem is extreme (i.e., you are far from the line at the right hand edge of zone 3), then water changes may be the best way to correct to the problem. In most cases, however, water changes aren’t necessary.

I would advise correcting this problem by adding a calcium chloride supplement until you have moved into the target zone (or zones 1 or 2 that you can then treat as described above) as shown in Figure 4. Almost any brand of calcium chloride will do (Kent Turbo Calcium, Kent Liquid Calcium, ESV, etc.). Certain other calcium supplements may also be OK (such as just the calcium component of the two-part calcium and alkalinity additive systems), but you do not want to add any alkalinity. You CANNOT use limewater or a calcium carbonate/carbon dioxide reactor to correct this problem. Any of the balanced calcium and alkalinity additive systems will move you parallel to the line at the edge of the zone, while you want to move over to it, and cross it.

If calcium is less than 400 ppm, I’d suggest using this handy online calculator7 to determine how much dry calcium chloride is necessary to move back to the target zone. Note that it is a minimum estimate because it does not know how much alkalinity you have, so it cannot know if you are only raising calcium directly (which it calculates) or are also precipitating calcium carbonate (when alkalinity is high this will probably happen, but is typically not a problem other than that it uses up some of what you add).

If the calcium is above 400 ppm in this zone (unlikely, but it does happen), then you can safely either do nothing until it drops and you need to add more calcium, and treat it as suggested in the previous paragraph, or you can add some calcium immediately, move into zone 1, and then just let it drop on its own.

[Boomer]

Boomer will prob tell me I'm talking out of my a#$e

Ok, lets start there

I don't think it is a balance issue. If he is adding nothing them where is the high pH and Alk coming from. More in question is why is the Ca only 400, so we would need more info Brucey like you said. For example, what is the Ca level of a fresh mix and also its pH and Alk. Your suggestion does have merit in that form. If a fresh mix is low in Ca, then the Ca is going up also. At this point the Zone he has is telling us nothing about the problem. It is not the first time this type of probelm has come about, but it is rare. If the DSB has an acid condition then there could be some dissolution of the aragonite raising the values, kind like a Ca reactor. This is quite coomon in FW tanks when people dump sea shell in them.

Alk is linked to Calcium as we all know

Yes and no but I know what you mean. Lets say it is more to a degree they are linked. For example, I could raise your Ca 100 ppm with no impact on Alk what so ever.

[cheeks69]

Thanx for the replys guys !
This was a question posed to me so it's not going on in my tank.
What happened was a friend overdosed MAGNESIUM a couple of weeks ago then he did several large W/C's to correct the problem he hasn't added anything and was waiting for the levels to correct themselves but his alk has increased for no apparent reason

Aragonite disolving would do that... do you have a DSB?

That seems like the only logical explanation but the ph would have to be real low wouldn't it ?

[Boomer]

It cuold get low enough in the sand bed. What Mg sup was he using ?

[cheeks69]

Boomer he was using Kent liquid magnesium ...
I would think that if the DSB is dissolving then it would also raise the calcium levels wouldn't it ???

[Boomer]

Kent = Magnesuium Chloride. Same as Turbo Calcium, only with Mg instead. Just another form of "snow melt"

Yes, the Ca you also rise, but if he was using a salt with low Ca and high Alk the pH and Alk would seem to be rising more than the Ca rise, ie, IO with 380 Ca and a pH of 8.3 and Alk of 11-12 dKH. If the Ca now was raised to 400, via disolution, that would be a 2.8 dKH increase. 11 + 2.8 = 13.8 dKH, with a followed rise in pH

[cheeks69]

Thanx Boomer !!
It seems that would be the only logical conclusion....