How do I keep alkalinity low while dosing kalkwasser for pH?

[dragonheart]

i have been using Kent kalk for my top off instead of plain ro water to help with my pH problem at night. my alkalinity has slowly risen from 9.0 to 13.4, does anyone have any solutions that would help me keep my alkalinity low but my pH correct...all and any help would be greatly appreciated..... thank you very much for your time.....sorry i'm not the greatest speller...lol

 

[reefpeeper]

what is your calcium level? and mag?

 

[dragonheart]

what is your calcium level? and mag?

to start my cal lvl was 440, mag was 1560 and kh was at 9.0,
and now its kh 13.1, mag 1740 and cal at 490

 

[nayrgaijin]

What else are you dosing? Kalkwasser only adjusts PH. It will also only MAINTAIN your Alkalinity and Calcium levels, Magnesium tends to slowly lower, but Calcium and Alkalinity shouldn't budge.

What's your PH at?

 

[dragonheart]

What else are you dosing? Kalkwasser only adjusts PH. It will also only MAINTAIN your Alkalinity and Calcium levels, Magnesium tends to slowly lower, but Calcium and Alkalinity shouldn't budge.

What's your PH at?

we have been dosing tech-m for bryopsis but when my alkalinity spike accured i hadn't been adding tech-m for a week... thats all we've been addin

 

[ReeferRob]

I would do a series of medium size water changes to get your params back to normal. You mag being that high is not a problem. Calcium will start to precipitate in the water. Alkalinity that high will start to burn SPS.

 

[RBursek]

What salt mix are you using and what is your water change regime? Dosing Kalk should not be raising your Alk that much if not at all, the same with Ca, it should not even maintain it, depending on tank needs. This article should you understand Kalk and the relationship with Ca and Alk.
What Your Grandmother Never Told You About Lime by Randy Holmes-Farley - Reefkeeping.com
Here is another one that may help
A Simplified Guide to the Relationship Between Calcium, Alkalinity, Magnesium and pH by Randy Holmes-Farley - Reefkeeping.com

 

[dragonheart]

our pH has been at 7.8 during the day and drops anywhere from 7.7 to 7.6 at night....our original pH was at 8.0

 

[dragonheart]

What salt mix are you using and what is your water change regime? Dosing Kalk should not be raising your Alk that much if not at all, the same with Ca, it should not even maintain it, depending on tank needs. This article should you understand Kalk and the relationship with Ca and Alk.
What Your Grandmother Never Told You About Lime by Randy Holmes-Farley - Reefkeeping.com
Here is another one that may help
A Simplified Guide to the Relationship Between Calcium, Alkalinity, Magnesium and pH by Randy Holmes-Farley - Reefkeeping.com

we where using tropic marine but ran out.....we had some left over reef crystals that we used up but now were going to try IO.....we also do 2 to 3 water changes a week thank you for the articals and your responses

 

[RBursek]

And here I am fighting to keep Alk up all the time doing 3qt WC a day with RC and dosing a gallon a day of kalk. I hope this helps, Going to IO myself here in a bit.
This thread contains data gathered by member Billybeau1. Thanks!

Here is a list of what I measured for the big three in a number of the salt mixes we use today. This is intended as a guideline and I, in no way, guarantee these figures. All I can say is they were all tested under the same conditions, with a number of different brand test kits, using the same methods for each test. I believe these numbers are reasonably what you can expect from these salts mixed at 35 ppt or SG 1.0264 @ 25 C.

Calcium​

Alkalinity​

Magnesium​

Aquatic Gardens
430
8
1240
Brightwell Neomarine
370
11
1140
CoraLife
560
9
1380
Crystal Sea Marinemix
340
9
1050
Crystal Sea Marinemix Bio-Assay
340
9
1050
D-D H2Ocean
450
10
1380
Instant Ocean (new)
400
11
1350
Kent
540
11
1200
Marine Environment
480
7.5
1450
Oceanic
580
8.5
1650
OceanPure
510
10
1320
Red Sea
400
8
1300
Red Sea Coral Pro
490
7
1300
Reef Crystals (new)
490
13
1440
Reefer's Best
420
11
1200
SeaChem Marine Salt
500
10
1400
SeaChem Reef Salt
540
10
1450
Tropic Marin
375
10
1230
Tropic Marin Pro Reef
450
8.5
1380
Tunze Reef Salt
420
9.5
1350

 

[dragonheart]

so i was just readin and they say that if you measure the carbonate hardness aka alkalinity of kalk- soution, you'll find a very high value but is not however not caused by bicarbonate or carbonte ions, which can be used by the corals, but hydroxide-ions . they hydrochloric acid in the alkalinity test cannot differ between these substances. so my question is how do i accurately test for my alkalinity?

 

[RBursek]

I do not understand your question/statement, are you trying to test your Kalk mix for its Alk content? Can not be done with hobby test kit, you will get a false reading. From Randy's article on Lime water
Limewater that is saturated with calcium hydroxide has a pH of 12.54 at 25ºC. It is actually recognized as a secondary pH standard. The pH is substantially higher at lower temperature (12.627 at 20ºC and 13.00 at 10ºC), and lower at higher temperature (12.289 at 30ºC; 11.984 at 40ºC). Saturated limewater has a conductivity of about 10.3 mS/cm at 25ºC, and contains about 808 ppm of calcium and 40.8 MEG/LITER OF ALKALINITY Slightly more calcium and alkalinity dissolve at lower temperatures, and less at higher temperatures. Of interest to chemists, a large fraction of the calcium in saturated limewater is present as the ion CaOH[SIZE=-1]+[/SIZE], with the remainder being Ca[SIZE=-1]++[/SIZE]. The CaOH[SIZE=-1]+[/SIZE] will instantly dissociate into Ca[SIZE=-1]++[/SIZE] and OH[SIZE=-1]-[/SIZE] upon its addition to aquarium water.

 

[dragonheart]

let me try to rephrase my question........i was never really the greatest at chemistry so some of this goes right over my head........i use the salifert test kits...... but what i was wondering is could i be getting an unaccurate readings do to the kalk?

 

[beaslbob]

let me try to rephrase my question........i was never really the greatest at chemistry so some of this goes right over my head........i use the salifert test kits...... but what i was wondering is could i be getting an unaccurate readings do to the kalk?

sure you could be getting inaccurate readings but your readings are not all that far outta line. could try getting a second opinion on alk.

that said low ph is a sign of carbon dioxide build up. just before lights out ph will rise through that action of macro algaes consuming the carbon dioxide. But they also return carbonates which could raise kh some. So I would add the macro algaes and then reduce the amount of kalk being added.

my .02

 

[dragonheart]

i just want to say thank you to everyone that has takin time out of there lives to give me advice and way to try and solve my problem......and again all and any advice is welcome.....please everyone have a great day!

 

[dragonheart]

so i was on reefcentral and got some suggestions.....just wondering what everyone thinks of this idea?
You can mix the Kalk weak. Even 1/2 saturated, it still has a pH near 12.

This is what I do as well...a little bit less than 1 tsp per gallon instead of the 2 teaspoons...I had the high alk issue before that with the saturated kalk.

PH stays at a steady 8.15 during the day

 

[RBursek]

I read it too, I may try it since my Alk runs about 11dkh with a 3qt daily WC with RC. I will not use my Hanna PH probe to check the 1tsp per gallon mix to check PH because it may throw it of for the tank use range and then need a recal.

 

[RBursek]

Dragonheart,
As far as your post and answer on RC, Bertoni varifies that cutting your Klalk dosage in have will still keeps it's PH at 12, he is one of the Chemical experts over there.

 

[20 gallon nano]

So if my ph stays stable at 8.3 does that mean my alkalinity will stay at around 12?

 

[KingBlingTX]

So if my ph stays stable at 8.3 does that mean my alkalinity will stay at around 12?

No. ALK drops as calcium carbonate is used by corals to grow.