To KALK or not to KALK?

MetroKat

New member
I tried to PM Randy Holmes but I'm not allowed so here goes:

I am a frustrated nano reefer that is getting mixed opinions on how to correct my tank chemistry problem. My gut tells me one thing but I get beat up on the forum I am on and by friends that are advanced and experienced reefers. I am into this for a year now.

First, a picture of my precious (RSM 130D with custom Sump, setup on Dec 25, 2011)
IMG_9734.JPG


An explanation of the problem will be lengthy. I have documented it in detail with the links below:

July 23 Aquarium water testing results (professional testing service)
Ammonia 0.000 (Good) My test shows the same
Nitrite 0.005 (Good) My test shows the same
Nitrate 3.5 (Good) My test shows zero
Phosphate 0.03 (Good) My test shows zero
Silica 3.5 (High)
Potassium 267 (Low)
Calcium 133 (Critical) My tests have always always always shown 490+
Molybdenum 0.0 (Low)
Stronium 22.9 (High)
Magnesium 1325 (Good) I test at 1500
Iodine 0.04 (Good)
Copper 0.01 (Good)
Alkalinity 1.9 meq/L or 5.0 dKH (Low) I test at 6.0 to 8.6

I spoke to Aquarium Water Testing service and they explained that the calcium was a reading of usable calcium, not total calcium which home tests measure. A 30 minutes conversation later they advised me to to raise Calcium using Calcium Chloride products.

Aug 5
What's going on with the tank chemistry:

Recent history of the tank shows I have had
High calcium (490+)
Low dKh (~7.0ish)
High Magnesium (1500+)
Undetectable Phosphates, Nitrates
So for the moment, let's take these levels as natural for my tank since I did not dose anything.

I had taken to adding buffer to raise the dKh and it worked (although I added it sporadically). Zeph suggested starting KALK because it works to maintain parameters, and to balance out 2 of them: Calc and Alk. My first gallon of KALK+2 didn't change the parameters in any direction. In hindsight, perhaps it was maintaining the existing parameters from fluctuating (keep in mind my tanks natural levels as mentioned above). Indeed many who read my thread and sources online suggest KALK is for people with the opposite problem: those that can't maintain calcium to appropriate levels. So I stopped KALK and went back to buffer which works for me as mentioned.

The trouble happened on July 27 when a 32oz of buffer solution got dumped in a 12 hour period in the tank. The dKH skyrocketed to 15. At this point I started my second gallon of KALK+2. Now keep in mind, I believe what KALK does is maintain your tanks parameters. The water for my water changes was Oceanic salt, not my usual Red Sea Coral PRO.

While everything in the tank looked happy, both at 15dKH and now, what resulted in the next few days was that the calcium dropped to 300 (!!), and dKH has been doing a slow but steady decline as well.

So why didn't KALK "maintain" the levels as before? I don't know much about all this chemistry business but it is possible that such a high level of dKH precipitated or "ate" or whatever the calcium to 300.

From the little I know, the 3 components of a reef tank: calcium, alk, mag have to be in balance. Everybody here can argue what the "right" balance is. For the sake of argument, and because this is my tank, the right balance for me is what I listed above.

Aug 5th levels
Calcium 300
dKH 7.6
Magnesium 1350+

Plan of Action:
5Gallon water change using my usual Red Sea Coral Pro salt
Stop KALK and get back to buffer.
Goal for 2 weeks (I'm travelling again): Maintain dKH at 10.

Aug 5: Coral health could not be better, honestly. I even see color coming back in some of the SPS that was showing signs of browning. Not out of the woods yet but I need to fix the calcium first.

Today:
Re-cap: My tank went from 490+ calcium to the 200-300 range in a very short amount of time. I did not change my salt mix or add new coral. I have a lot of coralline and SPS but equal if not more amounts of softies and LPS. The major fall in calcium happened on July 27 when 32oz of buffer got dumped all at one into the tank sky rocketing the dKH to 15. This caused the calcium what was previously always recorded at the 490+ range to fall to the 300 range.

I did a large water change and recorded I was back to my baseline of Calcium 470- on August 6. However that appears to be short lived also. On Aug 25 calcium measured at 250, dkh at 6.1 (10 days without waterchange)

So in went KALK into the ATO and I also started supplementing Part A, calcium supplement. Calcium has been at 300 but dkh is at 8.3. The KALK dosage is 3teaspoons in 2 G of water. My tank uses 1-1.5G of top off daily.

During all of this, let's talk about corals.
My zoanthids and palys are booming!
Some of the SPS are not happy. Some LPS are not happy. I see reduced polyp extension and the coral is not fluffy like it used to be. My HH brain coral is my indicator of tank happiness and it has not been really pleased for at least 10 days now. The same 10 days that I have been dosing KALK.

Initially I had high Calcium and low dKH (in the 7.1 range) and the article said not to dose KALK when this particular imbalance occurs (Zone 4)

"Many commercial alkalinity supplements will also be fine for this purpose, as long as no significant calcium is added. In general, I don’t prefer those that contain substantial borate. The alkalinity component of the two-part calcium and alkalinity additive systems would be OK. 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 left edge of the zone, while you want to move over to it, and cross it."

Initially when I refused to use KALK I was pounced on.
Then when I used a mild solution using a drip I was mocked.
Yeah I've been using 3tsp in 2 gallons in my ATO since the last week of August. Want to see my lovely KALK results?

IMG_9825.JPG
IMG_9854.JPG


I AM SO MAD!

My open brain coral, mancina, has been with me for a year. I look to this coral as in indication of the health of my tank.
Before KALK - all nice and fluffy. After KALK - tightly wound up and grumpy
IMG_9785.JPG
IMG_9857.JPG


However it is not all doom and gloom in the tank. The Z's and P's are very happy. I've had more polyp growth in the last 10 days than I have in the last 2 months.

And there are plenty of SPS that are doing just dandy
IMG_9810.JPG
IMG_9838.JPG


So. in conclusion, I have some questions
Is KALK helping me or not?
Why are my corals ****ed off?
What can I do besides more of Part A to get my Calcium back to the 400's?
If my water change gets my calcium high enough, should I be doing more frequent changes, like twice a wekk?
What can cause such a rapid absorption or decline of calcium in the water?

Thank you in advance for your help

Kat
 
Last edited:
Ok, so to be clear you are in zone 3 with low alk and cal?
You do have alot of corals in a small tank, maybe just raising your doses will help?
 
Wow. If it were me...
A) first, your coral are probably reacting to the extreme swings in water chemistry. Coral hate change and will be unhappy when your numbers are not stable. I don't care what my numbers are...they just need to be stable.
B) I would use Kalk as cruise control when your numbers are stable. Not to stabilize them.
C) I would also look to water changes before dosing. At least 5-10% per week. Better yet 5% twice a week.
D) add a little bit of 2 part daily as needed to help nudge the numbers.
E) use Kalk once your numbers stabilize.

Take it slow.
 
Is KALK helping me or not?

The calcium hydroxide ( klak) will add alkalinity and calcium in balanced proportions;the same proportions in which they are used and the same proportions when 2 part is used as directed. It can cetainly raise calcium and alkalinity and is easy to overdose.Whether it's" helping me or not" depends on: how much you dose ,how much you dose at once , and whether you overdose causing precipitation whereby the alk and calcium fall out of the water.

Rcommended ranges are:

Alk 7 to 11dkh
Calcium 380 to 450ppm
magnesium 1280 to 1350ppm

As long as you keep them in respective ranges and relatively steady there is no need to worry about any other balance.



Why are my corals ****ed off?

Probably because your alk and calcium levels are bouncing all over. Corals rely on a steady supply of alk and calcium at steady levels. Could be something else though. Salinity, temperature , ph, nutrient levels, lighing, flow , oxygen levels , all play a role .

What can I do besides more of Part A to get my Calcium back to the 400's?

Calcium chloride like turbo calcium or more of the calcium part of two part can be used to adjust calcium upward.



If my water change gets my calcium high enough, should I be doing more frequent changes, like twice a wekk?

Water changes do replenish calcium and alk to the levels present in the salt mix in the proportions of the water change.

Dosing alk and calcium in balance based on how much is being used will keep things going well whether it's kalk or two part.
Dosing just buffer will raise alk only and at high levels like 15 it will lead to excess preciptation and a loss loss of both alk and calcium.


What can cause such a rapid absorption or decline of calcium in the water?

Too much alkainity and/or calcium and high ph cause the calcium and carbonate( alkalinity) to form calcium carbonate ( like coral sand) and fall out of the water.

Magnesium helps slow this process but doesn't stop it.
 
Wow. If it were me...
A) first, your coral are probably reacting to the extreme swings in water chemistry. Coral hate change and will be unhappy when your numbers are not stable. I don't care what my numbers are...they just need to be stable.
B) I would use Kalk as cruise control when your numbers are stable. Not to stabilize them.
C) I would also look to water changes before dosing. At least 5-10% per week. Better yet 5% twice a week.
D) add a little bit of 2 part daily as needed to help nudge the numbers.
E) use Kalk once your numbers stabilize.

Take it slow.

This is good advice, and hopefully Kat's starting to see a consensus on this. :)
 
Ok, so to be clear you are in zone 3 with low alk and cal?
You do have alot of corals in a small tank, maybe just raising your doses will help?

Yes I went from Zone 4 to Zone 2 and now I am in Zone 3 (which is low cal high alk)

Historically, my tanks "natural" levels are Zone 4.
At this point I would like to go back to my tanks natural levels via water changes (except I don't know if this is a pipe dream) rather than dose to correct it. IF there is no alternative I'll dose more.
 
What are you dosing for alk?

Hi Mike,

At first, while the tank was in Zone 4, I dosed 8.3 buffer.
When the 32OZ of buffer got dumped in and changed my whole tank around, I stopped adding any ALK on top of the KALK.

With the latest parameters I have been dosing part A calcium to get that to go up (went up 50 points only) but because KALK was still being dosed, the ALK also rose from 6.1 to 8.3 without adding any additional ALK or part B.
 
Hi Kat,

Thought you could get away, eh? :wave:

All clear on how to handle this now?

Heyyyy! :) Are all the serious reefers on here? I was missing out.

Thanks for your help on this BTW. I value everyones advice, and I have found a huge gap between book knowledge and practical knowledge. On top of that a hobbyist, advanced or not, that can look at issues as they present themselves in another tank to determine the course of action is a jewel.

I'm still going to steal your ATO. :)
 
This is good advice, and hopefully Kat's starting to see a consensus on this. :)

YES! YES! YES! (I would still really appreciate Randy Holmes Farley to take a read through this in case I missed something)

So for the record, I stopped KALK 3 days ago and have only been dosing Part A, Hyp, per your suggestion yesterday I started dosing Part B albeit in a smaller dose than A.

I've got a 10% water change mix on the ready for today.
Water has been mixing since last night with 30TDS RODI water (yes I know, I'm working on the 30 tds too):
1.025
Calc 500
dkh 9.3
 
Is KALK helping me or not?

The calcium hydroxide ( klak) will add alkalinity and calcium in balanced proportions;the same proportions in which they are used and the same proportions when 2 part is used as directed. It can cetainly raise calcium and alkalinity and is easy to overdose.Whether it's" helping me or not" depends on: how much you dose ,how much you dose at once , and whether you overdose causing precipitation whereby the alk and calcium fall out of the water.

Rcommended ranges are:

Alk 7 to 11dkh
Calcium 380 to 450ppm
magnesium 1280 to 1350ppm

As long as you keep them in respective ranges and relatively steady there is no need to worry about any other balance.



Why are my corals ****ed off?

Probably because your alk and calcium levels are bouncing all over. Corals rely on a steady supply of alk and calcium at steady levels. Could be something else though. Salinity, temperature , ph, nutrient levels, lighing, flow , oxygen levels , all play a role .

What can I do besides more of Part A to get my Calcium back to the 400's?

Calcium chloride like turbo calcium or more of the calcium part of two part can be used to adjust calcium upward.



If my water change gets my calcium high enough, should I be doing more frequent changes, like twice a wekk?

Water changes do replenish calcium and alk to the levels present in the salt mix in the proportions of the water change.

Dosing alk and calcium in balance based on how much is being used will keep things going well whether it's kalk or two part.
Dosing just buffer will raise alk only and at high levels like 15 it will lead to excess preciptation and a loss loss of both alk and calcium.


What can cause such a rapid absorption or decline of calcium in the water?

Too much alkainity and/or calcium and high ph cause the calcium and carbonate( alkalinity) to form calcium carbonate ( like coral sand) and fall out of the water.

Magnesium helps slow this process but doesn't stop it.

Hey TMZ! Thanks for the response.

My KALK dosage details were in my original post. I do not believe 1 to 1.5 Gallons of KALK (mixed at 3tsp per 2G) dumped in 24 hours into a 45-50G system is over dosing KALK, what do you think?

My corals are ****ed off. However they aren't because the levels are bouncing all over the place. If anything they are completely steady. Again, this is in my original post. The changes I note and try to do happen over 2 weeks, not one day. Even when the 32oz of buffer got added to the tank by error, the level of DKH jumped (and the corals were SO happy for some reason) but then steadily declined over the next several days.

I have never seen a precipitation of chemicals in my tank.

Something to note: my mag has always been 1500, lowest has been 1350. Through all of this.
 
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