alkalinity

[rgb4136]

In testing my 29 gal tank, with a Salifert KH test kit, I find that the syringe with the re-agent goes empty without effecting the color of the fluid in the test vial, leading me to believe that my alkalinity level if off the charts. I have for sometime now been adding about 7.5 ml Kent Tech CB calcium buffer A&B to the tank. Yesterday I began a drip with limewater. My calcium is about 300ppm according to my Salifert calcium test kit. The tank has a protein skimmer which is working, as well as an Eheim filter suitable for tanks up to 66 gallons. I have about 30 lbs live rock and 50 lbs reef rock which is I hope turning to live rock. My water temperature is about 78.
Any comments or suggestions will be appreciated.

 

[Billybeau1]

Well if its not changing color with 1 ml of reagent, then it is more than 16dkh which is not good. Try filling the sryinge a second time and when the color changes add the two values together. (16 + whatever).

Then I would test a newly mixed batch of salt water and test that to make sure you dont have a test kit error.

Once you make those determinations then Randy can advise you what to do next.

 

[Randy Holmes-Farley]

I agree. Add more reagent to see then extent of the alkalinity issue.

Increase the calcium with calcium chloride, or just the calcium part of the Tech CB.

This article and calculator should help:

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

Reef Chemicals Calculator
http://home.comcast.net/~jdieck1/chem_calc3.html

 

[rgb4136]

Good Morning:
Thank you for the suggestions. I have tested again arriving at a dKH 38.4 with water taken from the tank. I also tested a batch of saltwater made up in the last few days, producing a dKH 42.2.
Calcium levels for the past two days have been about the same .38 (310ppm) I have been dripping Pickling Lime .75 teaspoon per quart of water for the past several days which has produced about 10ppm increase from 300 ppm on 3/30/2006.

I guess at this point I should fess up that I have been using filtered tap water.

Since all my critters seem to be doing well, I have not felt the need to do anything further regarding the water, but this situation seems to suggest that I should consider an RO. My reluctance is based upon the fact that RO wastes so much water.

I have a 10 gal tank which I don't use, absent your advice to the contrary, I will begin to introduce a measued amount of the Pickling lime directly into the tank on the basis of the calculator that you suggest.

Once again thank you both for your suggestions, anything further that comes to mind please don' t hesitate.

 

[Randy Holmes-Farley]

Something is very wrong. Tank water almost never has alkalinity that high.

What is the alkalinity of the tap water itself?

How much titrant did it take to arrive at that alkalinity?

Limewater is not a suitable way to raise calcium. It will push alkalinity through the roof, and may be part of your problem. You need a calcium only supplement such as calcium chloride.

This article should help:


Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

 

[rgb4136]

Further on the alkalinity problem

Further on the alkalinity problem

In testing the filtered tap water for alkalinity the results are 4.23 meq/L 11.8 dKH, leading me to believe that the addition of the Instant Ocean Sea Salt is driving the KH out of sight. --- Tested the theory mixed 1/2 cup Instant Ocean in 1 gal filtered tap water. KH went from 4.23 meq/L (11.8 dKH) to
13.17 meq/L (48.0 dKH). Also note that my Specific Gravity is on the high side 1.028+ My salt is old, I bought a 48# bucket about 18 months ago, could that be the problem? Does the specific gravity effect this at all?

Thanks again for your time and interest, any insights you might have will be appreciated.

 

[rgb4136]

Further on the alkalinity problem

Further on the alkalinity problem

In testing the filtered tap water for alkalinity the results are 4.23 meq/L 11.8 dKH, leading me to believe that the addition of the Instant Ocean Sea Salt is driving the KH out of sight. --- Tested the theory mixed 1/2 cup Instant Ocean in 1 gal filtered tap water. KH went from 4.23 meq/L (11.8 dKH) to
13.17 meq/L (48.0 dKH). Also note that my Specific Gravity is on the high side 1.028+ My salt is old, I bought a 48# bucket about 18 months ago, could that be the problem? Does the specific gravity effect this at all?

Thanks again for your time and interest, any insights you might have will be appreciated.

 

[Randy Holmes-Farley]

Wow. I'd stop using that tap water.

The alkalinity will probably drop on its own over a week or so.

 

[Billybeau1]

You may need to take a sample of your tank water to your LFS and have them check it. Sounds to me like test kit error, either the kit or the user. I would be real surprised if IO mixed that high in dkh. If your tanks inhabitants are doing well, I doubt your alk is that high

 

[rgb4136]

Thanks

 

[Randy Holmes-Farley]

:thumbsup:

Good luck.