Kalk dosing

[Sharkey18]

Hey everyone,

 

I need to start dosing kalk or a two part additive. I have been reading lots of posts lately about killing tanks by overdosing kalk so I have to admit I am terrified to do it. On the other hand, I would slow drip a predetermined amount over night when needed so there isn't much risk of a valve or some fancy equipment failing and I would never put enough in the drip bottle to OD so I guess I should be ok.

 

My question is what is the best way to do it for a small tank? (54 gal. corner, 10 gal sump)

The directions say to mix a gallon and add what is needed to the tank. If I do that I will add a few ml. and throw out the rest of the gallon. Or can I keep the gallon if I keep it closed and stir well before I use it again. Or should I just mix a lot less, like 1/2 or 1/4 gallon and just toss it after? My concern with that is the smaller volume mixed the less room for error, but saturated is saturated right?

 

Lastly: maybe I should just forget about kalk and use two part. It seems easier and safer? Anyone want to buy a cheap bottle of kalk?

 

I have many more questions but I'll post them one issue at a time.

 

Thanks so much, Laura

 

Current values:

KH = 8

calcium = 400

pH = 8.2

[flowerseller]

I've thought kalk was the way to go for the last 18 or so years.

[Highland Reefer]

+1 for Kalk.

 

Limewater (kalkwasser)

 

What Your Grandmother Never Told You About Lime

http://reefkeeping.com/issues/2005-01/rhf/index.htm

 

The Self Purification of Limewater (Kalkwasser)

http://www.advancedaquarist.com/issues/may2003/chem.htm

 

The Degradation of Limewater (Kalkwasser) in Air

http://reefkeeping.com/issues/2003-...ature/index.htm

 

Magnesium and Strontium in Limewater

http://www.advancedaquarist.com/issues/dec2003/chem.htm

 

How to Select a Calcium and Alkalinity Supplementation Scheme

http://www.advancedaquarist.com/issues/feb2003/chem.htm

[Origami]

Lastly: maybe I should just forget about kalk and use two part. It seems easier and safer? Anyone want to buy a cheap bottle of kalk?

 

Kalk is good. It can help stabilize your system if done right and you take the proper precautions against accidentally overdosing.

 

I need to start dosing kalk or a two part additive. I have been reading lots of posts lately about killing tanks by overdosing kalk so I have to admit I am terrified to do it.

 

Don't be. Just be thoughtful about it.

 

On the other hand, I would slow drip a predetermined amount over night when needed so there isn't much risk of a valve or some fancy equipment failing and I would never put enough in the drip bottle to OD so I guess I should be ok.

 

That's correct. If it's a slow drip and if the amount that were in the container were not enough to wreak havoc on your system if it were to be dosed quickly and completely, then you should be safe from accidents.

 

My question is what is the best way to do it for a small tank? (54 gal. corner, 10 gal sump)

 

First, have you established that you need supplementation? Does your alk fall noticeably between water changes, indicating consumption? If so, a slow drip into a sump using a gravity fed doser is one easy way to do it if consumption were low and you were up for maintaining the regimen. A lot of us compensate for evaporation entirely with the addition of kalkwasser - whether it be through a prescribed doser (drip, aqualifter, or peristaltic pump) or through an automatic top off system (which combines water level sensors with pumps of various kinds). I used to use an ATO to regulate my kalkwasser delivery but have, in the last couple of months, switched over to using a peristaltic pump on a timer. There's another method that I've not tried but I'll mention it here.

 

At the last meeting, I participated in on a conversation that Anthony Calfo was having with another WAMAS member. Anthony was suggesting at the time that you could just mix up a kalk slurry and just throw it in a high flow area all at once as a daily ritual and that things would be fine. Of course, I suspect that he runs much, much, larger systems than we do so I haven't a clue as to what such an approach would do to our systems.

 

At 54 gallons, I suspect that you're evaporating somewhere in the area of 1/2 gallon a day. Is that about right? In that case, I think you have a couple of easy options. One is a simple drip doser with a 1-gallon jug. The general rule of thumb for saturated kalkwasser is 1 teaspoon of powder to 1 gallon of RO/DI or distilled water. Since there are 600 drops to an ounce, dosing 1/2 gallon per day, equates to a drip rate of about 1 drop every 2 seconds (actually, it's 26-2/3 drops per minute). Drip rates on gravity fed systems, however, is not constant so you may have to play with the drip rate to get the dosing where you want it. You would mix up your first gallon and, every day, just refill the jug and add your kalk powder (1/2 tsp for 1/2 gallon of added water) and give it a good shake in order to make sure that the kalkwasser is saturated.

 

The other option is to make it part of an ATO system and to run your top off through a kalk stirrer, or to just premix your kalkwasser and dose it using a pump and float switch (or timer) system.

 

In either case, if you wanted to avoid a kalkwasser disaster, limit the amount of kalk or top off water that your top off system can deliver, not by trusting the delivery system, but by limiting the water and powder available. That way, if the delivery system fails, you're still covered.

 

The directions say to mix a gallon and add what is needed to the tank. If I do that I will add a few ml. and throw out the rest of the gallon. Or can I keep the gallon if I keep it closed and stir well before I use it again. Or should I just mix a lot less, like 1/2 or 1/4 gallon and just toss it after? My concern with that is the smaller volume mixed the less room for error, but saturated is saturated right?

 

Kalk keeps just fine. And, saturated is saturated. Remember, though, kalkwasser is the saturated solution that remains once you let the particle stuff - the stuff that hasn't dissolved - settle out. If you dose the particulate stuff, you're not controlling your delivery.

 

Now, that said, kalkwasser (or more properly, a saturated calcium hydroxide aqueous solution) does react with CO2 (in the atmosphere) to form a calcium carbonate precipitate. Those of us that have kalk stirrers see this as a crust at the top of our reactors. The formation of this crust often gives some protection to further reaction with CO2. If constantly stirred, the potency of the kalkwasser solution would ultimately deplete (though it may take a while) if it were not for the kalk powder reserve generally found at the bottom of the reactor column. In your case, however, if you're mixing up a gallon or a half gallon of the stuff each day, you'll be fine.

[Brian Ward]

I think the kind of stirrer each person uses contributes to the risk of a kalk overdose - also, how much kalk you put in the stirrer. I have a GSA stirrer, which runs 24/7 and VERY GENTLY agitates the kalk in the bottom of the stirrer - a bar rotates around 5 or 6 rpm in the bottom of teh stirrer. The effluent in the top is always clear. I've accidentally left my ATO in the ON state for an extended period of time (about 18 hours, resulting from stupidity and absent-mindedness on my part) and other than the flood in my basement and the drop in salinity in my tank, I had no problem whatsoever with a kalk overdose in my tank. I've seen another variant on kalk stirrers where a higher-rpm pump significantly agitates the kalk and puts undissolved particles in suspension. With these type of stirrers, you must be sure that you don't allow water from the stirrer to enter your tank while the kalk is still in suspension. This requires specific timing coordination between your pumps. Overall, kalk is an excellent additive that keeps up your pH and alkalinity and bonds to phosphate in your tank causing it to precipitate out. You just have to imagine what could possibly go wrong and be sure to protect against it.

[SeanCallan]

If you can get around using kalk then do so. Theres no reason for taking an unnecessary risk. I've got an SPS only tank and I have great growth and color without kalk. You will NEVER catch me using that on any of my tanks.

[ctenophore]

I use kalk on my small tank but not my big one. I don't recommend it for beginners due to the risk. It's very difficult to design a foolproof system. My advice is that if you are going to use it, and it can be very beneficial as others have stated above, try to incorporate the following principles into your dosing system:

 

1- Use a delivery mechanism that barely keeps up with your winter (or max) evaporation rate. If your delivery system is only capable of adding a given amount per day, say 500mL, and your tank evaporates 400mL per day, then your risk of major overdose goes way down.

 

2- Use multiple inputs to control kalk output. For example, I have my low-flow dosing pump controlled both by a pH probe and a float switch. If either input fails, I have the other as a redundant means of preventing overdose. If my float switch fails, the pH controller will shut off the doser at pH 8.5. This has saved me once already.

 

Good luck. I would use two part solution if I were you

Edited February 5, 2009 by ctenophore

[zotzer]

Anthony was suggesting at the time that you could just mix up a kalk slurry and just throw it in a high flow area all at once as a daily ritual and that things would be fine.

 

For all that trouble, what would be the advantage over a simple morning dose of two-part?

 

Tracy

[Coral Hind]

I would go with a two part solution. I have used Kent Marine's Super Buffer and Turbo Calcium products on smaller systems with great results.

[Origami]

For all that trouble, what would be the advantage over a simple morning dose of two-part?

 

Tracy

 

It's a matter of choice and technique, I suppose. Kalk is, by composition, a balanced additive, too, giving an equal part of calcium and alkalinity. (Magnesium would still have to be dosed, if required. But that's the "third part" of two part, isn't it?) Two part, on the other hand, gives you the ability to independently control each. Also, it's well known that some people dose two part using automated systems, which (I suppose) could lead to similar overdose risks.

 

BTW, I'm not advocating Anthony's suggested approach to dosing kalk - just repeating the rather unique advice that he was giving.

[Jon Lazar]

For all that trouble, what would be the advantage over a simple morning dose of two-part?

 

Tracy

 

I suppose the biggest draw is that kalk is pretty inexpensive over the long haul. One advantage to using kalk with all top off is you don't have to dose every morning, which could make your tank chores less demanding.

 

I use a calcium reactor on my tank.

Edited February 5, 2009 by Jon Lazar

[zygote2k]

I use milky kalwasser on my 40. Back in the day, Julian Sprung recommended using it this way and I have done so ever since. I use about a 1/4 cup daily and pour it directly into a heavy flow area in the sump or the 'fuge. It's almost impossible to have an overdose and way cheaper than having a kalk stirrer or reactor. Only takes a minute or so a day.

[Sharkey18]

Wow. Thanks everyone so much for their responses. This group has been such an amazing help to me and the generosity of the members with information still astounds me. Thanks so much.

 

I will read through all the responses again and decide what to do, but I think the information provided is exactly what I needed and should be pinned for newbies like me who are just getting ready to start using kalk or a two part. I've read a lot of the articles on it and understand it but the personalized attention and opinions really do help.

 

Laura

[Smoothtriqueter]

not hijacking just jumping in.

 

I find that my calcium is usually fine (above 400) with just my H2O changes. But My dKH drops very quickly from 8 or 9 after the H2O change to about 5 or 4 in less than a few days. I have been adding just part 1 of the B-Ionic 2 part. Is this a problem if I am adding one should I add the other, even though my Ca is ok?

[Origami]

Alk drops 1 meq/l (or 2.8 dKH) for each 20 ppm of calcium drop. That's why you see what looks like a drastic drop. Both are actually dropping, it's just that your test kit probably doesn't have the resolution or that you're just not noticing the very slight decline in calcium. If you're using a balanced additive the proper way, you can compensate for consumption with dosing.

 

You can learn a bit more about this here: http://www.advancedaquarist.com/issues/nov2002/chem.htm

Edited February 5, 2009 by Origami2547

[Smoothtriqueter]

ok been looking how would I go about adding backing soda? I have been reading that 1 TBS raises dKH ~1, do I just a some to my tank or mix in some top off water?

[Origami]

ok been looking how would I go about adding backing soda? I have been reading that 1 TBS raises dKH ~1, do I just a some to my tank or mix in some top off water?

 

Ack. How much it raises your alk depends upon how much water volume you have. There is no simple rule like 1 TBSP to raise 1 dKH.

 

Use a reef chemistry calculator like this instead: http://reef.diesyst.com/chemcalc/chemcalc.html

 

Simply enter the water volume of your system in the box at the top center; enter your current alk, desired alk, and (where it says "Pick a Product") click on "Baking Soda (not baking powder)." The calculator will then tell you how to mix up and dose to get the desired effect.

[Smoothtriqueter]

Thanks a mill for that link that will help out a bunch