Who's Using BW Kalk+2?

harlequinreefer · Oct 18, 2011

I've been using Brightwell Aquatics Kalk+2 as a secondary dosing method on top of my 2 part system. I dose Kalk+2 as a topoff through my kalkreactor, and I must say it has worked very well. I just wanted to get some feedback from other people who are using it.

arotbart · Oct 18, 2011

Bw kalk +2

Love it...really good stuff. I mix it with about 25 ml of vinegar with about 1 1/2 tsp per gallon of RO water. I mix a 2 1/2 gallon batch about 2x/week, and drip it via BRS doser at night and couple hours through out the day. I have a CA reactor, but I like using kalkwasser as supplement.

only thing i have noticed over a long period of use is that my MG started creeping up really high to 1550-1600. So, what I do now is I just use any high quality Kalk mix (currently 2 little fishes) and every 3rd or 4th batch I switch back to BW K +2. That seems to keep the MG from taking off like it was.

harlequinreefer · Oct 18, 2011

I like it a lot too, it compliments my 2 part nicely. Steady Alk, Cal, Mag & Stro for me. I switched from regular kalk to this 6 months ago, definately cuts down my 2 part dosages.

efrain torres · Oct 18, 2011

Is very expensive versus other kalk .I USED KALK FRON BULK REEF AND WORK VERY NICE .

harlequinreefer · Oct 18, 2011

Regular kalk doesn't contain magnesium hydroxide or strontium hydroxide

Dave3112 · Oct 18, 2011

I use it. I can't use it everyday though. It jumped my Mg up to 1700 so I use it in my kalk drip 3 times a week now. the rest of the time I just use Ms. Wages pickling lime.

BCORAL · Oct 24, 2011

The BW Kalk +2 works well for me.

skinz78 · Oct 24, 2011

I've had good luck with it, my tank demands a pretty high amount of Mag so I haven't had any issues. I even have to dose Brightwells Magnesion to keep up.

Troylee · Oct 24, 2011

Been using it since it hit the shelves... Pretty sure I got a bunch of others to use it also.... I love that stuff!!!! Haha

rhcpnut1 · Apr 6, 2014

Aquarium Chemistry: Magnesium And Strontium In Limewater ? Advanced Aquarist | Aquarist Magazine and Blog

dulgee · Apr 16, 2018

sorry to resurrect this old thread, but i thought some practical proof of what has been stated would be welcomed.

i just sent this comment to brightwell aquatics, thought i'd share here:

I have a problem with your Kalk+2 product. I had doubts that this product could work as advertised because magnesium precipitates in high PH, and since a saturated kalk solution is a very high PH environment, logic dictates that the magnesium would just fall out of solution and rest on the bottom of the container... well, most kalk solutions have some sediment after it becomes fully saturated, so i originally thought that's what it was. However at such a high cost, i did further testing, and even at a 50% saturation there is quite a bit of precipitant on the bottom, which leads me to believe it is the magnesium. Which also tells me that when i dump out the slurry at the bottom its all magnesium, and my drip is only providing pure lime water, which i can buy at a fraction of the cost. Further evidence indicates that there is no significant increase in magnesium in my tank, in fact, i still see the typical consumption rate. Perhaps this product is more useful in a kalk stirrer which will release the slurry into the water column where the crystallized magnesium would dissolve into solution once in a more sea-like PH environment.

I suggest a recommended use within a kalk stirrer be advertised and a notice that magnesium will fall to the bottom unless kept in suspension in a stirrer.

Randy Holmes-Farley · Apr 16, 2018

This thread predated my time running this forum, but there should be no doubt: kalk+2 is NOT a desirable product.

There is no answer they can give that will suggest otherwise.

Here's a copy and paste from an earlier post of mine:

Unfortunately, it is a very poorly designed product that won't work. It has very little magnesium in it, but even that will precipitate out in limewater as magnesium hydroxide.

Really, this is a pitiful product. Not enough magnesium to be useful even if it worked, and it won't work.

It is a marketing gimmick.

One other comment with respect to the magnesium.

IMO, it is risking being disingenuous to name the product kalk + 2, because normal calcium hydroxide has magnesium in it as an impurity. I expect all Brightwell's product is with respect to magnesium is the natural impurity of magnesium.

I show in the article linked below that bulk supplied calcium oxide and hydroxide have that amount of magnesium or more already in it. So to try to claim it as a plus is misleading, IMO.

Magnesium and Strontium in Limewater
http://www.advancedaquarist.com/issues/dec2003/chem.htm

Montiman · Jun 21, 2018

I have used this product for years after a fellow aquarist recommended it to me. I have absolutely no idea why as I have read all the documentation showing the magnesium should not stay in solution but I notice I need to dose less Mag than I do when I use TwoLittleFishies, SeaChem, or Kent Kalk. It is also cheaper than all these other kalk options in my area. I do use a pump driven stirer so most everything is getting dosed. Perhaps this is why it works for me.

Randy Holmes-Farley · Jun 21, 2018

Montiman said:
I have used this product for years after a fellow aquarist recommended it to me. I have absolutely no idea why as I have read all the documentation showing the magnesium should not stay in solution but I notice I need to dose less Mag than I do when I use TwoLittleFishies, SeaChem, or Kent Kalk. It is also cheaper than all these other kalk options in my area. I do use a pump driven stirer so most everything is getting dosed. Perhaps this is why it works for me.

Sorry, no. That cannot be it, and it is nothing more than a gimmick claim. Even if you got all of it to the tank, it is almost none.

They tell you how much is there, and it is almost none, and is, in fact, less magnesium than is naturally present as an impurity in bulk food grade material from Mississippi Lime Co.

http://brightwellaquatics.com/products/kalk2t.php

Guaranteed Analysis
Calcium (min) 54.20% (542,000 ppm), Strontium (min) 1.00% (10,000 ppm), Magnesium (min) 0.15% (1,500 ppm)

Magnesium is present at 0.28% of the calcium level. That is far less than is used by most reef tanks. Corals and coralline algae range from a low of 0.13% to 11%.
https://www.advancedaquarist.com/2003/10/chemistry

But let's see how much that actually corresponds to.

Suppose that you dose 1 dKH of alkalinity each day. That means you are dosing about 7 ppm of calcium each day, and only 0.28% of 7 ppm = 0.02 ppm of magnesium per day.

So even in a YEAR of additions of Kalk+2, you have only added 7 ppm of magnesium.

There's no way you can detect that 7 ppm per year against a background of water changes and salinity changes, and then correctly claim that so much magnesium was added that your apparent need for additional magnesium was noticeably less.