Alkalinity issues

[jennm]

As I mentioned before, this is an issue where one's mileage (and opinion) may vary.

Albert Thiel has written that he recommends 5.35-6.45 meq/L

Dallas Warren has recommended 3.0-6.0 meq/L

http://www.reefs.org/library/talklog/d_warren_090797.html">http://www.reefs.org/library/talklog/d_warren_090797.html</a>

Seachem Salinity's target alkalinity is 3.2-3.8 meq/L according to their literature.

It would seem that there is a huge difference of opinion even among the scientists.

It should also be noted that while many of us, myself included, have posted conversions of meq/L to dKH, that meq/L is referring to *total* alkalinity, not just carbonate and bicarbonate alkalinity (KH or dKH). As such, total alkalinity can and will be higher than if one is just measuring carbonate and bicarbonate alkalinity. When I test, I test total alkalinity. (Includes borate & hydroxide alkalinity), not just dKH.

I'll reiterate: Alkalinity is only one part of the picture. If other parameters are not where they ought to be, problems can arise. Cause or effect? Depends on the situation.

I have no problem with somebody challenging or disagreeing with me, that's the purpose of a discussion. If anything, it should prompt each of us to do further independent research. Clearly, this is one of those areas where there are many differences of opinion.

Jenn

 

[jennm]

1PERCULA;453161 wrote: My Alk was reading at 7. I understand that it should be between 12-16. My calcium is 460-480, PH 8.4 and I don't have a Mag Test kit. I added Reefbuilder to my tank yesterday and the Alk went up to 10 temporarly, but when I checked it today it was back to 7. Reefbuilder says to add the product twice a week, however, I was wondering if I should dose it daily until it builds up and maintains the proper readings. I am checking the Alk every 24 hours. Should I dose it again or wait another couple of days?

To answer the original question... yes, you can dose it daily.

Per: http://www.seachem.com/Products/product_pages/ReefBuilder.html">http://www.seachem.com/Products/product_pages/ReefBuilder.html</a>


[QUOTE=]BEGINNER: Use half a level teaspoon per 150 L (40 gallons) twice a week. Dissolve in at least one cup of freshwater. Check alkalinity every 2 weeks and adjust dose or frequency accordingly.

[B]ADVANCED: Check alkalinity, then follow dosing regimen above until alkalinity is adjusted to 4–5 meq/L. Each dose will raise alkalinity by about 0.25 meq/L. Size or frequency of dose can be adjusted, but do not exceed 1 meq/L per day. Thereafter, use as required to maintain alkalinity. [/B]

EXPERT: After determining the alkalinity consumption rate, set up a continuous drip system. Use the following formula to determine how much to add to your top-off water: t=0.05va (t=teaspoons to add to top off water, v=volume of tank in gallons, a=amount to raise alkalinity in meq/L). For example, if you want to raise your alkalinity by 1 meq/L in a 50 gallon tank, then you would add 0.05x50x1=2.5 teaspoons into the top-off water. [/QUOTE]

 

[ichthyoid]

JennM;453508 wrote: As I mentioned before, this is an issue where one's mileage (and opinion) may vary.

Albert Thiel has written that he recommends 5.35-6.45 meq/L

Dallas Warren has recommended 3.0-6.0 meq/L

http://www.reefs.org/library/talklog/d_warren_090797.html">http://www.reefs.org/library/talklog/d_warren_090797.html</a>

Seachem Salinity's target alkalinity is 3.2-3.8 meq/L according to their literature.

It would seem that there is a huge difference of opinion even among the scientists.

It should also be noted that while many of us, myself included, have posted conversions of meq/L to dKH, that meq/L is referring to [B]*total* alkalinity, not just carbonate and bicarbonate alkalinity (KH or dKH). As such, total alkalinity can and will be higher than if one is just measuring carbonate and bicarbonate alkalinity. When I test, I test total alkalinity. (Includes borate & hydroxide alkalinity), not just dKH.[/B]

I'll reiterate: Alkalinity is only one part of the picture. If other parameters are not where they ought to be, problems can arise. Cause or effect? Depends on the situation.

I have no problem with somebody challenging or disagreeing with me, that's the purpose of a discussion. If anything, it should prompt each of us to do further independent research. Clearly, this is one of those areas where there are many differences of opinion.

Jenn[/QUOTE]

Not to take sides, but...

That is a valid distinction Jenn, and one that many do not fully understand or always interpret correctly. It helps to know how it was tested. In one of Randy Holmes-Farley's articles, he point this out, as well as the fact that SeaChem is the only test that measures 'total' alk (if I remembered that correctly) not just dKH which is assumed to be the 'total' by many, if not most in the hobby. Randy also illustrates that SeaChem also adds extra borate, which will skew most tests unless offsets are allowed for.

Additionally he comments on the use of phenolphthalein titrations in particular, here he says it best...

<p style="text-align:left"><span style="font-family: Times New Roman">"Some test kits also provide a different dye for a different measure of alkalinity. Frequently, this other dye is phenolphthalein. This dye has a color change between pH 8.2 and pH 9.8. In fresh water, carbonate is almost completely converted into bicarbonate at pH 8.3, and that is the purpose of <span style="color: #000000">[IMG]http://www.me.cc.va.us/dept/ietech/water_wastewater/distance_learning/courses/ENV211/atest2.htm"><u>phenolphthalein titrations</u></a></span>: to determine alkalinity in freshwater due to carbonate only (discussed in detail below). This test serves no purpose in a reef tank or seawater for two reasons: 1) the water is probably already more acidic than the endpoint of this dye, and 2) the carbonate in seawater is not completely converted into bicarbonate at this pH anyway. That is, even if the pH were higher than 8.3 (say, 8.6), titrating down to the phenolphthalein endpoint will not effectively "count" all of the carbonate because in saltwater there will still be substantial carbonate present at the phenolphthalein endpoint."</span>
<span style="font-family: Times New Roman"></span>
Links to a couple of his articles below. These should be read several times (IMO) to fully comprehend this very complex topic. Much of where we need to be chemically is in the 'trend' and not the absolute number. I think of alkalinity as related to pH and calcium, as I do RedOX potential to overall aquarium health. The number itself is not as important as where it is headed. The temptation of chasing the 'spec/number' should never overshadow the overall balance of parameters-IMO.

[IMG]http://www.reefkeeping.com/issues/2004-05/rhf/">http://www.reefkeeping.com/issues/2004-05/rhf/</a>

[IMG]http://www.advancedaquarist.com/issues/feb2002/chemistry.htm">http://www.advancedaquarist.com/issues/feb2002/chemistry.htm</a>

 

[jennm]

My recommendations are based on testing total alkalinity using a Seachem test kit.

In the first article you cited, Bill, even RHF says:

I suggest that aquarists maintain alkalinity between about 2.5 and 4 meq/L (7-11 dKH, 125-200 ppm CaCO3 equivalents), although higher levels are acceptable as long as they do not depress the calcium level.

I believe that is the crux of the "argument" as it were. Alkalinity is only one piece of the puzzle. OP posted that CA is 460-480 which is a bit high, IMO, but there is no MG value known.

And I do concur that chasing numbers shouldn't overrule the search for a balance.

Jenn

 

[ralph atl]

from RC

http://www.reefcentral.com/forums/showthread.php?t=1772160&highlight=seachem+test">http://www.reefcentral.com/forums/showthread.php?t=1772160&highlight=seachem+test</a>



I have read levels as high as 20x the amount of borate. They may have reformulated it. I have seen no published levels. This makes determining your true carbonate/bicarbonate content of the alkalinity in your tank very difficult to determine. The carbonate/bicarbonate content of alkalinity in your tank is very important, in that this is the part that coral and other organisms utilize to grow.

Randy performed tests on the [B]<span style="color: #ff0000">SeaChem</span>[/B] borate kit and the Salifert Boron kit. He found that the [B]<span style="color: #ff0000">SeaChem</span>[/B] kit left something to be desired and not suitable for this purpose. On the other hand, he found that the Salifert Boron kit was satisfactory for this purpose.

Boron in a Reef Tank (and its effect on pH buffering)
[IMG]http://www.advancedaquarist.com/issues/dec2002/chem.htm"><span style="color: #000088">http://www.advancedaquarist.com/issues/dec2002/chem.htm</span></a>

The [B]<span style="color: #ff0000">Seachem</span>[/B] Borate Alkalinity [B]<span style="color: #ff0000">Test</span>[/B] Kit
[IMG]http://www.advancedaquarist.com/issues/june2003/chem.htm"><span style="color: #000088">http://www.advancedaquarist.com/issu...e2003/chem.htm</span></a>

The Salifert Boron [B]<span style="color: #ff0000">Test</span>[/B] Kit
[IMG]http://www.advancedaquarist.com/issues/sept2003/chem.htm"><span style="color: #000088">http://www.advancedaquarist.com/issu...t2003/chem.htm</span></a>

 

[ichthyoid]

mysterybox;453538 wrote: from RC

http://www.reefcentral.com/forums/showthread.php?t=1772160&highlight=seachem+test">http://www.reefcentral.com/forums/showthread.php?t=1772160&highlight=seachem+test</a>



I have read levels as high as 20x the amount of borate. They may have reformulated it. I have seen no published levels. [B]This makes determining your true carbonate/bicarbonate content of the alkalinity in your tank very difficult to determine.[/B] The carbonate/bicarbonate content of alkalinity in your tank is very important, in that this is the part that coral and other organisms utilize to grow.

Randy performed tests on the [B]<span style="color: #ff0000">SeaChem</span>[/B] borate kit and the Salifert Boron kit. He found that the [B]<span style="color: #ff0000">SeaChem</span>[/B] kit left something to be desired and not suitable for this purpose. On the other hand, he found that the Salifert Boron kit was satisfactory for this purpose.

Boron in a Reef Tank (and its effect on pH buffering)
[IMG]http://www.advancedaquarist.com/issues/dec2002/chem.htm"><span style="color: #000088">http://www.advancedaquarist.com/issues/dec2002/chem.htm</span></a>

The [B]<span style="color: #ff0000">Seachem</span>[/B] Borate Alkalinity [B]<span style="color: #ff0000">Test</span>[/B] Kit
[IMG]http://www.advancedaquarist.com/issues/june2003/chem.htm"><span style="color: #000088">http://www.advancedaquarist.com/issu...e2003/chem.htm</span></a>

The Salifert Boron [B]<span style="color: #ff0000">Test</span>[/B] Kit
[IMG]http://www.advancedaquarist.com/issues/sept2003/chem.htm"><span style="color: #000088">[IMG]http://www.advancedaquarist.com/issu...t2003/chem.htm">http://www.advancedaquarist.com/issu...t2003/chem.htm</span></a></a>[/QUOTE]

+1-exactly, and the speciic type of test/titration used also.

I think this topic makes it [I][B]very[/B]</em> easy to fall into the trap of 'apples to oranges', while leaving us with the perception that it's all 'lemonade' (if that makes any sense-lol).

I love the fact that there are so many passionate, knowledgeable people in this community that force me to really think! Getting it right is what matters most.

 

[ralph atl]

a few issues:

1. my Elos test kit (I believe almost all) measures total Alk

http://www.reefcentral.com/forums/showthread.php?t=1674554">http://www.reefcentral.com/forums/showthread.php?t=1674554</a>

please read the above thread.

[B]Now for reefers that use Seachem Reef Salt only[/B], it is appropriate to keep a higher level of Alk, since they have like 2 to 20 x's the amount or Borate than any other salt & natural seawater. Only Carbonate alk is what is utilized by corals. That much Borate will make you think that are have 8dkh, when it's really 6-7.

I use Seachem Reef want my alk on the low side of around 8, so I shoot for 10.

There would be no reason to go above 12, however.

 

[ichthyoid]

a few issues:

1. my Elos test kit (I believe almost all) measures total Alk

http://www.reefcentral.com/forums/showthread.php?t=1674554">http://www.reefcentral.com/forums/showthread.php?t=1674554</a>

please read the above thread.


Thanks for the link, I did read it.

Also,
I went to the Elos website, and their test (<span style="font-size: 12px">AquaTest KH) </span>measures dKH or KH, which both refer to 'carbonate hardness' and which Elos uses interchangeably. Unless I missed out on another kit they make, that kit does not appear to measure 'total alkalinity' but only 'carbonate alkalinity'. Below is a copy from that web page:

<span style="color: blue">The ideal value of KH in aquarium is:
- for seawater aquarium [B]7 dKH° to 10 dKH°[/B]
- planted freshwater aquarium [B]3 dKH° to 7 dKH[/B]°</span>

Reference link: [IMG]http://www.eloseurope.com/en/index.php?page=shop.product_details&flypage=shop.elos_flypage&product_id=22&category_id=7&manufacturer_id=0&option=com_virtuemart&Itemid=87">http://www.eloseurope.com/en/index.php?page=shop.product_details&flypage=shop.elos_flypage&product_id=22&category_id=7&manufacturer_id=0&option=com_virtuemart&Itemid=87</a>

Also,

Regarding tests which measure total alk, I was referring to Randy's article referenced earlier, and again quoted below. It is upon his summary that I made the statement about Seachem's alk test being the [B]only one[/B] to test total alk.

<p style="text-align:left"><span style="font-family: Times New Roman">"Finally there is the German term dKH (degrees of carbonate hardness), or just KH (carbonate hardness).Strictly speaking, it is the same as the carbonate alkalinity (AC in equation 8). Unfortunately, it is a very confusing term, as it has nothing to do with hardness. Further, it has been corrupted by the marine aquarium hobby to mean the same as total alkalinity, and every test kit that tests for dKH with a single titration is giving total alkalinity. [B]<span style="font-size: 13px">The only kit that I am aware of that even makes a distinction between carbonate alkalinity and total alkalinity is one of the <span style="color: #000000">[IMG]http://www.seachem.com/en_products/product_pages/0924_RS_mgnsm.html"><u>Seachem kits</u></a></span> (Reef Status: Magnesium, Carbonate, & Borate) and it thankfully doesn’t use the term dKH at all.</span>[/B] Consequently, most hobbyists should think of dKH as simply another measure of total alkalinity. The results obtained with such a kit (dKH) can be divided by 2.8 to yield the alkalinity in meq/L. "</span>
<span style="font-family: Times New Roman"></span>
Reference link (just before the 'conclusion'): [IMG]http://www.advancedaquarist.com/issues/feb2002/chemistry.htm">http://www.advancedaquarist.com/issues/feb2002/chemistry.htm</a>


I agree with below 12 KH for alkalinity, but am open to higher possible readings for reasons we have both illuminated.

Perhaps things have changed since Randy wrote the article. Am I missing something?

 

[ichthyoid]

I think I discovered my oversight.

<span style="font-family: Times New Roman">"...and every test kit that tests for dKH with a single titration is giving total alkalinity"</span>
<span style="font-family: Times New Roman"></span>
Titrations force the conversion of carbonate to bicarbonate right off the bat anyway, so all we really measure is the conversion of bicarbonate to carbonic acid (excluding the 3% of borate, and smidgens of the others). This gives a good approximation of the total alkalinity. I see now. Thanks!

(also explains why high borate throws single reagent titrations off)

 

[ralph atl]

ichthyoid;453802 wrote: i think i discovered my oversight.

<span style="font-family: times new roman">"...and every test kit that tests for dkh with a single titration is giving total alkalinity"</span>

titrations force the conversion of carbonate to bicarbonate right off the bat anyway, so all we really measure is the conversion of bicarbonate to carbonic acid (excluding the 3% of borate, and smidgens of the others). This gives a good approximation of the total alkalinity. I see now. Thanks!

(also explains why high borate throws single reagent titrations off)

bingo