For those dripping kalkwasser

[tbmoore]

Saw this on another board and thought it might be usefull to somebody.

Dripping Kalkwasser: 101
There has been quite a bit of interest as of late in dripping kalkwasser. So I have decided to write in detail about it. I hope I get the words to come out right!

After buying all of the hyped calcium and buffer products on the market… after trying to figure out how much and when to dose…. after testing and testing and the levels never balance out… after all the money spent on these products… many people resort to dripping kalkwasser.

It is a very intimidating methodology, starting with the word kalkwasser itself. What does it mean? Well, it is German for limewater. Can you throw some lime in the water and dose… nope. It is actually calcium hydroxide mixed with water (reverse osmosis/deionized water is best). Which, by the way, is the same thing as pickling lime. Ball’s or Mrs Wages Pickling lime is a cheaper and near equal substitute for the expensive brand name Kalk mixes available at your local fish store.

So why dose kalk? What’s the goal? Pretty much all corals and coralline algae will benefit from a kalk drip. It provides the calcium and hydrogen ions (that turn into carbonate with existing carbon dioxide in the tank) that are necessary for calcification of corals and coralline algae. When dripped correctly, it can provide rock solid test results for pH and, in turn, calcium and alkalinity. Alkalinty, our measure of carbonate, determines the stability of pH. Kalkwasser has a high pH, so it is usually dripped at night (or non photoperiod) when the pH of the tank is low. (Photosynthesis has stopped, so CO2 is high, lowering pH) This keeps pH stable as all of this limewater is being introduced to your tank. If you have a 24-hour a day lit refugium, photosynthesis is never stopped and kalkwasser can be dripped 24/7 as well. I believe this leads to the most stable conditions.

Added info: Kalk needs to be dripped into a tank that has previously established balanced levels of calcium and alkalinity. (see balancing table) If one of these levels is outta whack... i recommend using a two-part additve to get them settled before dripping kalk. I use ESVs B-ionic, but any two-part additive will work.

Here is a balancing table.
Alk/ dKH/ Calcium
0.00 0.00 360
0.50 1.40 370
1.00 2.80 380
1.50 4.20 390
2.00 5.60 400
2.50 7.00 410
3.00 8.40 420 (Near sea water)
3.50 9.80 430 (My average)
4.00 11.20 440 (My goal)
4.50 12.60 450
5.00 14.00 460
5.50 15.40 470
6.00 16.80 480 (My goal for my frag tank)
6.50 18.20 490
7.00 19.60 500
end of added info

Kalkwasser is best for tanks with high evaporation rates, as the kalk can be mixed into the topoff water and dripped together. This method isn’t necessary, but I find it to be the easiest. I simply calculate how much water is evaporated from my tank daily and figure out how many drips must fall in a given amount of time to equal my 24hr evaporation loss.n (this gives my needed “make up water”) Then, determined by my tanks needs (amount of coralline algae, amount and types of corals) I add the kalk to the make up water. Tanks with low evaporation rates and high calcium needs should probably seek other alternatives.

How do you mix kalk? Your kalk mix will change as your tanks needs change. There is not one set recipe for all tanks. It will take a lot of adjustment in the beginning to get it right. As said before, RO/DI water is the best. A good starting point is 1 teaspoon (~5ml) of calcium hydroxide per gallon of water. The saturation point of calcium hydroxide in 1gal of water is ~2 teaspoons. (there are always exceptions as discussed in the vinegar section at the end) Above this point, it will precipitate outta solution leaving a residue at the bottom or at the top of the water. This must not be added to your tank as it will wreck your pH. Also, when storing a kalk mix, make sure the container is air tight or the CO2 in the air will turn the hydrogen ions into bicarbonate which will turn in to calcium carbonate. It is important for new batches of kalk to settle for an hour before dripping… this ensures a good mixture and any precipitate that may happen will be in the bottom of the container. You only want to drip the clear solution.

How to add kalkwasser? As said before it is dripped over a slow period of time. Dumping a jug of kalk in an aquarium will result in disaster from pH spike. Drip the kalk into a high flow area to allow the solution to disperse through the tank well. If not dripped in a high flow area… precipitation can occur. Kalk is gravity dripped via tubing from a container. The tubing is pinched to regulate drips. The tubing outlet of the container is usually an inch above the bottom of the container so that the precipitate settled in the bottom doesn’t enter the aquarium. This precipitate can clog the tubing as well as wreck your water chemistry as mentioned. Keeping the outlet above the precipitate level also ensures that no minerals found in less than perfect kalk mixes enter the tank. Once the container is empty and the drip period completed. Rinse and empty the container and start again. Kalk dosing is only effective as long as it is a continuous process. Obviously, the larger the container the longer you can go b/w mixing. For those of you looking for a good product to dose kalk with, I have had good success with a 5 gal kent aquadoser. It costs about 25 bucks and holds enough to last me about 7 days. This will of course change pending your tank size and evaporation rate.

A well mixed kalk solution will test super high levels of Ca … near 1000ppm. (as you can see, another reason not to dump it all at once)

It is best to test for Ca and alk at the same times each day. If over the course of 5-7 days your Ca is falling… then add more calcium hydroxide to the mix. If it is too high, add less. Once you find a stable level.. you can continue to mix the same rate each time. Over weeks of stability, testing is less necessary. But, remember, the more your corals grow, the more new specimens are added, the more coralline algae grows… the more the demand for Ca. So periodic testing should be done. ( I am down to one testing session a month)

What does vinegar have to do with kalkwasser? Vinegar (acetic acid an organic carbon source) allows us to cheat the calcium hydroxide saturation levels. By being acidic, it lowers the pH of the kalkwasser, allowing more calcium hydroxide to be added. Bacteria loves carbon and turns it into carbon dioxide, which helps with the production of bicarbonate and carbonate. The acetic acid also aids in the growth of denitrifying bacteria that are so useful in getting rid of excess nitrate by turning it into harmless nitrogen gas.
So, how much vinegar do you add? Well, as suggested by Guy Comstock (AKA Bang Guy), be careful with vinegar… if you are already having algae problems… or other issues from mal-nutrients such as nitrates… don’t fuel the fire with vinegar. The extra carbon dioxide will be readily used by algaes during photosynthesis and result in outbreaks of cyanobacteria( not an algae, but give me some slack), hair algae, etc.

Back to the question… how much vinegar? If you are new to kalkwasser, skip the vinegar at first… if you are brave enough, then: the max saturation of vinegar in 1 gal of water is 48ml. I suggest starting your vinegar experimentation at ¼ this rate and working your way up as needed.

Once again, feel free to supplement, correct, or question. I dont pretend to be a chemistry expert, but thought this would be a good write up.

I hope Bang or someone will write about dripping into the protein skimmer for phosphate removal. I dont know enough about it to explain it.

If you get all of this.. then go

[reeferpuffer]

cool

[ShagMan]

Look, I'm dragging up a thread from the dead!!!

I'm gonna spark a debate.

I DUMP kalk (pickling lime), three heaping tablespoons a night, DIRECTLY into my sump. My PH has a spike of < .2 after I do this. I've gone through two bags of pickling lime in a month's time. I've started doing this after watching Jeff (KrazyPlace) put a teaspoon's worth directly into his 29G setup. Kalk in undissolved form spews out the outputs into the tank.

My Ca is slowly rising past the 430 mark.

I'm recovering from a low alk problem (my alk was down to 5DKH, I'm correcting this with a baking soda mix)... other than that, tank is great. You guys have seen pics of the tank, the corals are pretty happy... the few probs I'm having are minor (GSP's aren't happy), and I believe are due to the DKH being way too low.

Comments??

[KrazyPlace]

Just for the record... if for any reason Josh's tank does crash, I had nothing to do with it!

I do indeed 'dump' pickling lime into my sump directly into the suction of my pump. This is based on the 0.2 pH rise theory as outine by Bob Fenner and his lime slurry method. See http://www.wetwebmedia.com I just skip the RO water part of it.

My hard corals are doing awesome.

[Scott]

I add some to my top off water. I have not measured the ph increase but the ph of my top off water (one gallon with ~1/3 teaspoon) is 9.0 so I doubt that adding two gallons of top off to about 90 gallons of tank volume would raise the ph more than a tenth. I use this in addition to a calcium reactor mainly to make sure that my ph doesn't get too low from the excess CO2.

[KrazyPlace]

...I'm recovering from a low alk problem (my alk was down to 5DKH, I'm correcting this with a baking soda mix)... other than that, tank is great...

Remember the ion balance theory here. Salt water is made up of NaCl (Na+ and Cl-). By adding Kalk we are adding Ca(OH)2 which will quickly become just Ca+ in the tank. The carbonates come mostly from CO2 absorbed in the water through the skimmer and other 'turbulent' regions of the tank. There is no Na+ or Cl- added by doing this.

When you start to add baking soda you're adding Na+ and CO3-. The CO3- is used, but the Na+ is just more ions in the water. If you will 'balance' this with CaCl2 then you will be adding the other half of the salt (Cl-).

For small shift in water parameters it doesn't make any significant difference, but since you, like me, seldom if ever change water then you must be careful in the long run.

[ShagMan]

You lost me at "Remember".

So you're saying that I should make up the two-part that randy recently posted the recipe for? I thought that mix didn't help the buffering?

The above two paragraphs is why I love Jeff's nickname "Mad Scientist"

[ShagMan]

P.S. I checked my magnesium content last night, it's still 1200 or so, so I didn't have to add any. Are there any more trace elements I should watch for, since I don't do water changes? I'm dosing strontium like a mad man every night, since it's zeroed out... that kent stuff in the bottle is pretty weak, I added 30ml two nights ago, and no noticable rise, I added 60ml last night... I've used 1/3rd of the bottle already, gotta love a large tank

[Scott]

Mg should be at least 3 times the Ca level so around 1300 is a good start. Mine was 1150 and I added a whole bottle of Kent Tech M over the course of a week and it only raised it to 1220, so it takes a lot.

[KrazyPlace]

You lost me at "Remember".

So you're saying that I should make up the two-part that randy recently posted the recipe for? I thought that mix didn't help the buffering?

The above two paragraphs is why I love Jeff's nickname "Mad Scientist"

If your calcium is high and your alk is low, then refer to this article: "CHEMISTRY AND THE AQUARIUM by RANDY HOLMES-FARLEY" http://www.advancedaquarist.com/issues/nov2002/chem.htm You are in zone 4.



Oh ya... all images are being reused without the expressed written permission of the author. I do give him full credit though!

You need to move the alk up without affecting the calcium.



I also use the information below without permission, but with full credit given to my Mad Scientist idle: Dr. RANDY HOLMES-FARLEY.

Zone 4 problems are also a little harder to correct. It is typically caused by overdosing calcium RELATIVE to alkalinity, but does not necessarily imply that alkalinity is either to 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.

If this problem is extreme (i.e., you are far from the line at the left hand edge of zone 4), then water changes may be the best way to correct to the problem. In most cases, however, water changes aren’t necessary.

If alkalinity were less than 4 meq/L (11 dKH; the most common situation in zone 4; shown in Figure 5), I would advise correcting this problem by adding an alkalinity supplement until you have moved into the target zone (or zone 1). For systems with a pH of 8.2 or above, baking soda (sodium bicarbonate) is a good choice. For systems with a pH below 8.2, washing soda (sodium carbonate) is a good choice (though use some baking soda too if the correction is a large one and the pH gets too high; that is, above pH 8.5 or so).

What the hell does this mean? You don't have enough CO2 in your tank! Mmmm… I wonder why?



Are your nitrates at 0 or maybe even negative? (just kidding about the negative!) If so, maybe it wouldn't be a bad idea to cut back on the lighting in your refuge. Don't you run 24/7? Is your pH high (indicating low CO2)?

Light + plants = less CO2 and more O2. I fought my pH for a year before adding the refug. I was stuck at 7.9. Now I'm in the 8+ ranges... I haven't changed anything, except I added a refug.

Sorry to everyone for the long post, but... The CO2 in the tank is converted to carbonates while adding Kalk. That is why Kalk is its own best 'balanced additive', but not quite. It needs CO2 to make the carbonates.

This is just a theory, but I would adjust the alk using the above mention method, then work to correct my CO2 deficiency. I think you have a good problem here my friend.

Anyone want to cry BS on this theory? I'm not an expert, so let's here some responses!

[KrazyPlace]

If you're not completely tired of me yet then... http://reefkeeping.com/issues/2002-04/r ... /index.htm

This article explains all this stuff in more detail. It’s a very good article. Read the last section, it discusses the balance of calcium and alkalinity and the relationship with CO2.

Another solution is to aerate the water more.

[Brandon]

<b>GREAT POST</b>
My parameter are where they should be, so I'm not really in zone 4, Alk=10.6, Ca=410, but I have to wonder how effective kalkwasser is for me now.

Hrm.. I generally have pretty high ph, sometimes 8.4-8.6, but have no refugium, and a decent fish load. Could be my skimmer, or maybe I need a new ph test kit. I've always had high ph though, since I started the tank.
I have never thought about the need for co2 with dosing kalk, now I'm going to have to go back and read the article from randy.

[ShagMan]

Welp I'm on the right track then! I'm dosing 4 TBLSP of 6:1 baking soda/washing powder to get the alk/DKH back up... it's at about 2.5 meg/L right now, and slowly coming up.

Yep, my PH stays in the 8.2-8.5 range.

Yep, you're right about the macro... it's DEFINITELY limited only by nutrients, when I feed heavier, it grows faster... that amount that's in my hand and in the bucket, I pull that much out every 30-60 days or so... and yep, my nitrates/nitrites/ammonia is always ZERO, and I mean zero. SOOO, yes, I'm using up CO2 and generating oxygen at a pretty fast rate... I do arreate a lot, run a skimmer 24/7 and also have a "bubble curtain" unintentionally in the refuge, which the macro seems to love.

I'm hoping my tank turns around once I get the strontium and alk back into the 'zone'... right now with my ca at 440 or so, I'm just barely in "zone 4" on the picture above.

Jeff you're my hero, all that stuff is a little too far over my head.

[KrazyPlace]

Is your refug lights on 24/7?

[KrazyPlace]

I read this WetWebMedia.com:

Converting Caulerpa Refugium to Misc. Algae

Question: I have heard of people using xenia as a nutrient export. Are there benefits? downsides?

Response: briefly stated... Xenia is fast growing, weakly noxious and fairly stable. It is also quite saleable. That makes it useful as an "animal filter"... best regards, my friend. Anthony

Xenia is an animal, not a plant! That means you could switch to Xenia instead of macro. You should see an increase in CO2 due to reduced consumption and increased production of it.

Has anyone tried this in the group or read a good post regarding it? I'd like to see it.

Just a thought.