New way to dose Ca... And fun too!

My dkh has been out of whack recently due to dosing with kalk so i sat down and did some organic chemistry to try and get to the bottom of this problem... Well good news, I got to the bottom of it, my dkh is spot on now, I am saving a TON of money on calcium supplements now, and I feel very accomplished for figuring out this chemistry

so i previously mixed my kalk with a bit of vinegar to help get more Ca in my limewater. this also added a source of carbon to my tank so i had to stick with the vinegar in some way shape or form...

The benefits:
New method produces at least triple the amount of calcium in suspension
A lot easier on your dkh
Uses DRASTICALLY less material
pH is not caustic anymore
it dissolves completely so no worries about particulate or precipitate
IT HAS MAGNESIUM AND STRONTIUM, as kalk does not!

Some background:
this may get a little technical so if chemistry bores you skip it. If you want to be convinced, read it...

The equilibrium of this reaction lies MUCH MUCH MUCH farther towards products than that of kalk. The vinegar dissociates a H+ ion and happily accepts the Ca+ ion due to higher molecular stability. More Ca+ is pulled from the CaCl2 because it: 1. is an ionic solid and dissolves readily in polar liquids and 2. the electronegativity of Ca allows more to be picked up by the vinegar and form a stable bond and 3. the Ca ion has the ability to make pi bonds with oxygen on acetic acid. This isnt on the valence layer, according to the molecular orbital theory it is likely to form this type of bond. All of these points show why it is spontaneous for more Ca to be pulled out of solution and why it is more stable when bonded in such a fashion. sorry if that bored you... now on to the good stuff!

The mix:
1.) Purchase a container of seachem Reef Advantage Calcium
2.) In a 2 liter bottle measure out a portion of vinegar. (start with a little and increase at your discretion)
3.) Dissolve the Reef Advantage Calcium in the vinegar. You do not need to put a lot in... Depending on how concentrated you want it, generally one tablespoon is still a lot! (IMPORTANT: as the bonds are broken heat is released. this is from the bonds being broken as the H+ is ripped off the acetic acid and replaced with Ca+. The heat shows that it is spontaneously happening at a very fast rate.)
4.) Cap bottle and mix to finish reaction (there should only be a VERY little bit of liquid at this time and all of the powder should have dissolved almost immediately after dumping it in when touching the vinegar)
5.) Fill the rest of the bottle with RO/dH2O.
6.) You now have a super concentrated Calcium solution that is mostly just plain water!
It is probably in your best interest to dilute this farther when dripping. i do about 200-300ml of solution and dilute to 1000ml with RO water in my dosing container. (when diluted as such, the 2 liter will last for over a week and assuming that each tablespoon is around 12g of Reef Adv Ca, a 500g container of Ca will last for a year!!!)

Your pH will be slightly acidic: 4-6
Your [Ca] should be: 500-700+ppm
NOTE: This solution will have a small amount of dissociated chlorine in it. If there is enough energy to get two chlorine molecules to bond this will produce a small amount of chlorine gas. Just dont be stupid and sniff the bottle and this will not harm you. However, most of it stays in solution so you can put in a drop or two of de-chlorinator if your worried about it, otherwise it will bind with sulfates in your tank.

Now for the kicker ... After hypothesizing this and then mixing up a primary batch I decided to email seachem about it. After a week of waiting for them to get back to me, this is what they had to say:

"Hello Trent,
I'm so sorry for the delay in response. You can do the same process with the Reef Advantage Calcium, but just be sure to monitor your pH and alkalinity. I actually did this in the lab using a liter of water with about ~12 G of ReefAdvCa & acetic acid resulting in an acidic pH. What is happening is the dissolution of calcium, magneisum, and strontium and the pH will remain acidic due to the use of vinegar. Before the mixture you where making probably resulted in a higer pH due to the use of base (Kalkwasser) and an acid (vinegar) somewhat neutralizing one another depending on amounts used. The carbon source (CH3COOH) will still be availale. This mixture will result in higher calcium numbers compared to kalkwasser."

So there you have it, straight from the seachem chemist lol... a MUCH more practical, cheaper, and effective way of dosing Ca. If you dose this make sure you are monitoring your Ca until you get a feeling for how fast it fluctuates, as it will rise quicker than with any other method!

Thank you for your interest and I hope you can try this method out too!
Trent

 

very interesting. seems like this would save quite a bit of money..

 

yes! trust me, it saves a ton of money... and thats something you dont come across often in this hobby lol

 

Well I will give it a shot as im all out of Turbo CAl so its a good time to try somethink new.
I think I would have to dose it in my ATO water 19lts/5gl. I normaly just dissolve my Turbo Cal in it and thats it ,so I guess it shouldnt be much different (just the vinegar)
The vinegar is my only question, what quantity is a good starting point /examplary point ?

 

well if you want to be really conservative id use between 10-20 ml or just enough to dissolve the calcium mix. go easy on it your first time, then you can step up the vinegar each time

 

freakin awesome bro im doing it now

 

well its been a few months now and I thought I'd just post some info on my resaults
Im still using my first mixed batch and my calcium is sitting at 420 constantly.
so as far as value goes I think its a great alternitive.

 

wow this is amazing think someone could post some pics of the solution (how much in a 2 liter, how dosing, etc) ?

 

Dingo

Im using SeaChems advantage calcium to maintain calc level
can you define "portion of vinegar" please
how much vinegar per level spoon of advantage calc?

in a 70 gallon reef set up, would the QTY of vinegar required to make this calcium saturated mix, have any negative effect on the tanks PH?

how does the resulting mix perform in terms of staying in solution
can it be used in a dosing system, or will a stirrer be required in order to keep it mixed and prevent it settling ?

Steve

 

I pretty much grasp the chemistry dingo but do we want; "What is happening is the dissolution of calcium, magneisum, and strontium and the pH will remain acidic due to the use of vinegar."
Do we want those elements to remain acidic?