Idea?

[SB-129]

Can someone more chemistry-savvy than myself answer a basic question?

A calcium reactor uses CO2 to drop the pH in the chamber to the point that aragonite will dissolve. What pH level is obtained?

I ask because I know that vinegar, a common Kalk additive used by reefers has a fairly low pH, something like 4... Would aragonite stored in vinegar dissolve? And if so, would the resulting solution be capable of dissolving Kalk powder or would its composition have been changed by contact with aragonite, rendering it incapable of reacting with calcium hydroxide?

I suppose my question is, if used vinegar which had been used to "steep" aragonite in my kalkwasser would I be putting any more calcium into the mix? More importantly, would I be introducing anything undesirable?

 

[SB-129]

And another question: why can't a calcium reactor be set up to enrich make-up water with calcium rather than plumbed to the main system? If something went wrong, only a batch of RO is at stake. Couldn't CO2 be bubbled through a chamber full of aragonite and make up water using fairly minimal equipment?

 

[cubera]

Huh??

 

[esmithiii]

Cubera: Enough with the "huh??"s already.

The pH of the effluent is dropped by adding CO2, which will come out of solution at some point due to oxygen exchange. Althogh vinager (acetic acid) would probably dissolve the aragonite, it would permantly alter the pH of your tank to the extent that it would kill all life in the tank.

E

 

[Mouse]

Too much trouble, What? Mixing Kalk and Vinegar, erm yea right. Its such a hassle mixing Vinegar with Kalk, i would rather spend my time cleaning precipitation from the surface of my tank???

1 liter RO
1/2 tablespoon Kalk
15 ml Vinegar

Yep i can see the problem here, where do you get half a tea spoon from.

Adding C02 to the aquarium allong with Kalkwasser should have the same effect as using vinegar, basically providing the Kalk with free ions so that it doesn't precipitate out of solution. Besides that the reaction chamber size is so small in consideration of the total aquarium volume that the ammount of C02 needed to lower the PH is tiny, far to small to affect the aquarium. And thirdly if the reactor is dripping into the aquarium then C02 will be released into the air should it recieve too great a flow. So what are you worried about???

[ October 29, 2001: Message edited by: Mouse ]</p>

 

[SB-129]

I suppose you're right, I'm simply intrigued by any alternative to a US$500-$700 calcium reactor setup. The cost of these devices is outrageous, and I don't know if my marriage can withstand another $1K in the tank.

BTW, maybe it's not the 1/2 teaspoon but rather the liter thing... A liter of makeup water wouldn't go very far in my tank, and I don't know what I'd measure a liter of anything with in the first place.

For those of us using quaint old U.S. measures: Mix 1 cup distilled, white, 5% acidity vinegar vigorously with at least 3 tbsp. Kalk powder (or pickling lime as most of us use). Thin the mix with a little water if necessary. Dump this into a 5 gal. container of makeup water, mix well, and voila, spiked Kalk.

It is recommended that you start slowly, though, using 1/4 cup of vinegar initially and checking your readings/livestock.

[ October 29, 2001: Message edited by: SB-129 ]

[ October 29, 2001: Message edited by: SB-129 ]</p>

 

[SB-129]

Actually, provided that the vinegar is dissolved in a solution saturated with Kalk, it doesn't alter the pH of either the Kalkwasser or the system significantly,

Craig Bingman wrote an excellent article on the use of vineger to increase the calcium carrying capacity of Kalwasser:

http://www.animalnetwork.com/fish2/...bio/default.asp

Besides, the pH of saturated Kalkwasser is nearly 12, just as high above our tanks' range as vinegar is below (at 4).

What about the possibility of treating makeup water in a chamber full of aragonite with CO2... Sort of a Nilsen/calcium reactor arrangement. It seems that this would lower the potential for damage to the system due to CO2 overdose, and thereby reduce the cost of a calcium reactor device.

[ October 29, 2001: Message edited by: SB-129 ]</p>

 

[gbtower]

Sounds like too much trouble.

Just make sure you have enough aeration in your tank , or have your calc reactor output to your skimmer intake, and you shouldn't have to worry about co2 overdosing.

 

[afss]

does anyone on the board use this vinegar-kalk solution? do you find it helps?
thanks
Scott
_________________
Mercedes F700

 

[SB-129]

I use it, but have only done so for a couple of weeks. Some folks have been using it for up to a year with good results. Others have complained that it provoked algae blooms.

It IS higher in calcium than just regular water and calcium hydroxide powder. It still doesn't meet my calcium needs but it's better than plain Kalk until I can afford a reactor.

 

[afss]

any one else use it?
How much percent wise does it increase the concentration?
thanks
Scott
_________________
Mercedes Limousine W126

 

[davelin315]

I'm curious about the idea of using a kalk reactor on top off water. I have never tested my local pH, or the pH of the water out of my RO unit, but if it is low enough, what would be the problem with running your drip over aragonite and allowing that to run into your system? Would a slow slow constant drip of freshwater dissolve aragonite in the same way as a calcium reactor and add the elements you are seeking to begin with? SB-129 poses a very interesting and possibly money saving question! Anyone out there with the know-how to answer?

 

[kipreefer]

Well first of all if you allowed your top off water to run through aragonite it would barely do anyhting. Not to many tap water supplies are below 6.0 becasue if it was anywhere below that it would burn you when ever you drank it. You need ot remember that each nunber in the scale is that many times stronger tehn the last number. So even though ti doesnt seem like there is much of a diffrence between six and seven it is actually double the strength. But now that i think about it calium reactors just create carbonic acid when it the CO2 reacts with water and that is considered a weak acid maybe at about 5.5 justa guess. So it may not need a real high PH to make the base soluble. it is just a week acid wont break down a strong base. It can but you need tons for the moles to cancel out. But i would just use a calcium reactor becasue calcium carbonate just extract from itself and will return to the surface if the water just like a soda. Just my two cents of what i remember form chemistry a few weeks ago.

 

[kipreefer]

To answer top question. It would break down the Kalkwasser if is has enough of the acid reamining. If all the acid was nutrealized while reating witht the aragonite it wouldnt break down much it would just form a homogonous mixture.kind of liked freshly stirred kalkwasser.

 

[randy holmes-farley]

SB:

<< Would a slow slow constant drip of freshwater dissolve aragonite in the same way as a calcium reactor and add the elements you are seeking to begin with? >>

The best that you can hope for in dissolving aragonite in fresh water is about 1 meq/L alkalinity. That's on the order of 25x less potent than limewater. It might be useful to some people, but it's really not very much.

<< Would aragonite stored in vinegar dissolve? >>

Sure. You would convert it into calcium acetate, which is very soluble. I've dosed my tank with small amounts of calcium acetate with no problem. Using a lot of this, however, will be dumping a lot of acetate into the tank, and some have reported that this drives some unusual (undesirable) organisms.

IMO, it would be an interesting and inexpensive system if one dissolved aragonite (like Home Depot Sand) in vinegar, and then used a plastic trash can of this material for top off.

Perhaps someone will try it.

 

[Mouse]

I have just started to use Vinegar in my Kalk and one thing i have noticed is that i no longer have any precipitation. So i guess thats a bonus. Appart from that i dont think ive been using it long enough to come to any conclusion as to its effectiveness, allthough from what i have seen of my corraline growth it does seem to have increased.

P.S. i also have a calcium reactor.

[ October 31, 2001: Message edited by: Mouse ]</p>