- Pharma Kalkwasser (Calcium Hydroxide) - Bulk Reef Supply
Ultra-pure Kalkwasser for Reef Tanks!
BRS Pharma Kalkwasser is not your typical calcium hydroxide. It is made from an ultra-pure source that contains extremely low amounts of aluminum and compared to traditional kalkwasser you can actually see the difference. If you are adding Kalk to your ATO reservoir or a reactor, you will find that BRS Pharma Kalkwasser mixes faster with fewer impurities and is even more potent than the others, meaning you will not have to use as much, saving you money in the long run.
Two Sizes Available:
- 2 Pounds
- 4 Pounds
Using Kalkwasser (Calcium Hydroxide)
Kalkwasser is the easiest method to maintain calcium and alkalinity levels in a reef aquarium not to mention low cost. With a few different methods to implement it, if your corals are growing and you need to add calcium and alkalinity, you will more than likely find multiple benefits from using kalkwasser. Being the only way to add calcium and alkalinity from a single solution along with helping elevate the pH of your aquarium to helping purify your ATO water even further, there are plenty of reasons to add kalkwasser to your ATO reservoir or set up a Kalk reactor or drip system. By far the most common application for kalkwasser is by adding it to your tanks top off reservoir and then relying on the auto top off system to deliver small amounts of saturated kalkwasser solution throughout the day.
We suggest using BRS Calcium Chloride, BRS Sodium Bicarbonate, and BRS Magnesium for General Adjustments to elevate and balance your aquariums parameters before using Kalkwasser.
How to Use Kalkwasser with an ATO System
Step 1. Test and adjust your aquariums calcium, alkalinity, and magnesium levels using BRS Calcium Chloride, BRS Sodium Bicarbonate, and BRS Magnesium for General Adjustments.
Step 2. Start by establishing the proper amount of kalkwasser to mix into your aquariums top off water reservoir.
- Low Demand - 1/2 teaspoon per gallon of top off water
- Medium Demand - 1 teaspoon per gallon of top off water
- High Demand - 1 1/2 teaspoons per gallon of top off water
Step 3. With RODI water fill your top off reservoir & mix in the proper amount of kalkwasser then allow the solution to settle for 30 minutes before using.
DO NOT OVERMIX: Excess mixing and air contact will decrease the potency of kalkwasser.
Step 4. Place your ATO systems pump or intake line is place 1/2" to 1" above the base of your reservoir, ensuring only the clear slurry is being dosed.
Step 5. Activate your ATO and monitor the pH of your aquarium as the kalkwasser solution is being dosed, not exceeding increases of 0.20 pH. Your ATO should be pumping water into a high flow area of your sump or display tank to help prevent precipitation. Adding kalkwasser too fast may result in precipitation rendering it ineffective.
Step 6. Monitor your aquariums calcium and alkalinity daily, adjusting the strength of the kalkwasser solution in your top off reservoir as necessary.
Note: We highly suggest using a pH controller to prevent against pH spikes and overdosing.
Refilling The Reservoir
Simply refill your container with fresh RODI water and add the proper amount of kalkwasser per gallon of new RODI water and mix. It is recommended to clean your ATO reservoir regularly, though you do not have to every time you replenish your ATO container.
Maximum Dosage - 1 1/2 teaspoons per gallon of top off water
One of the limitations of kalkwasser is its 1 1/2 tsp. per gallon saturation point. Anything more than that will simply fall to the bottom of your reservoir and become essentially useless. If your aquarium is requiring more calcium and alkalinity added than what kalkwasser can keep up with there are a few solutions;
- Start 2-part dosing
- Increase your aquariums evaporation rate with fans
- Vinegar method (experts only)
How Does Kalkwasser Work?
Kalkwasser or Calcium Hydroxide Ca(OH)2 when mixed with fresh RODI water contains a perfect balance of alkalinity and calcium ions that can be added to your aquarium to help supplement what your corals consume when they grow. It is pretty easy to see where the calcium is derived from but the alkalinity can be a little more difficult to see, and when Kalkwasser is added to your saltwater tank a simple reaction takes place converting the hydroxide into available bicarbonate ions. Essentially the CO2 in your water and atmosphere will react with the hydroxide ions creating bicarbonate ions and increasing your tank's pH, due to less available carbon dioxide.
Ca(OH)2 = Kalkwasser
OH- + CO2 = HCO3 = Bicarbonate
OH- + HCO3 = CO3-- + H20 = Carbonate + Pure Water
Want to see how BRS Pharma Kalkwasser stacks up against the others?
Mixes Extremely Well! By Clay on 6/25/2020Clay would recommend this product to a friendI just received my 4lb bag of BRS Kalk today. After raising my pump a little inside the RODI reservoir, I mixed the powder into the RODI water and let it settle. To my surprise there was almost no residue that had collected on the bottom of the reservoir! Granted this is the first time mixing it into this container, I am very impressed at how clean it mixes with my RODI water! Great product!
Great stuff By Chris on 12/27/2019Chris would recommend this product to a friendI’ll never use Mrs Wages again! This doesn’t make dust clouds when you open and close the bag, mixes up nice and is cheap.
Fresh and clean By JaaxReef on 4/17/2019JaaxReef would recommend this product to a friendThis Kalk is clearly superior to other offerings. The powder is much easier to scoop without getting everywhere and it mixes fast and clean. Glad I switched over and I’m excited to see the results in my tank with less impurities being added from this new cleaner kalkwasser.
Okay By Ken on 2/22/2019Ken would recommend this product to a friendThis new Kalk powder does not work well in my Avast stirrer, the residue packs tightly in the bottom and has stopped my stirring mechanism from spinning. I like the old powder better. With this I have to scrape it out of the cylinder bottom to clean it.
Old version was better By Chas on 2/10/2019Chas would recommend this product to a friendI've been using BRS Kalk for years. I really preferred the old version, it was less expensive, came in a better container and had less residue after settling. The new stuff is OK, and I'll keep using it, but I'm not sure why they changed a great product to make it worse.
One other thing to add about using kalk By Addison on 10/21/2018Addison would recommend this product to a friendIf you’re going to use kalk in an ato, you should be test your ph and alkalinity daily. This ensures you won’t nuke your tank and that you’re keep things stable. If you choose not add this simple test which your tank will benefit from anyways then you’re the only one responsible for your tank issues not brs.
Brs Pharma Kalk By Addison on 10/21/2018Addison would recommend this product to a friendI’ve been in this trade as a hobbyist for 18 years and spent the last 4 years as a professional. None of the other kalk provide by other companies is as strong as this stuff. On top of that it clears almost instantly after the initial mix and saturation. I use a gravity fed ato and I mix my solution then after it has settles it’s poured into the holding res. The mixture’s then delivered to my tank via a float valve. The single most effective means of help stability in an sps tank other then a CRx.
There’s a few reviews that make no sense kalk is going to leave residue/sediment regardless. If that’s a problem either you don’t understand the premise of how kalk is utilized or you need to find a deferent method that suits you better. Secondly you should always add your kalk mixture slow if you use a digital ato with an actual pump you need to use a aqualife or dosing pump to be safe. Not a pump that’s going to do 100’s of gallons per hour after head loss. Ultimately gravity fed ato setups are going to be safest and most effective because they literally can match your evap rate. Please stop bashing a great product for your own discrepancies.
Not as Good as I Hoped Initial thoughts) By DavidS on 7/12/2018DavidS would recommend this product to a friendHaving used other brands (ESV, TLF and Seachem) with equally good results, I nevertheless disliked the messy sediment that accumulated from said products.
I was encouraged to use the BRS Kalkwasser as it claimed to leave much less residue. Unfortunately, after just one night of use, I looked in the following morning and was surprised to see a comparable amount of sediment at the bottom of my reservoir.
There is no reason to think it will not perform, as well as, or better, as other marketed brands, at a lesser price.
But if anyone is buying it in the hopes there is less sediment, compared with other brands, they might be disappointed.
Didn't have any luck By Alex on 5/28/2018Alex wouldn't recommend this product to a friendFollowed advice from the BRS team and then was told the info on the package was incorrect? Nuked a 5 year established tank doing the ATO method suggested. Calculated evap rate, etc. BRS support contradicts advert and instructions printed on label. Know what you are doing and do your own research if you decide to use this; don't listen to BRS support or printed instructions.
Kalkwasser By Rafaylina on 3/17/2018Rafaylina would recommend this product to a friendThis kalkwasser is easy to mix. Also easy to use with an ATO once you have your parameters dial in..
Works great By Jack on 1/16/2018Jack would recommend this product to a friendThis product is a great beginner way into keeping your cal and alk up with just your ato. I've been running it over a year now and my nano reef tank is doing great.
Great for any hard coral out there By Jack on 12/5/2017Jack would recommend this product to a friendI purchased the 1 gallon and it's last me about a year on my two nano tanks keeping my calcium up and my corals are growing great
I have the Neptune ATO in a 5 gallon ATO WaterBox ATO chamber in the Sump.
Can I mix this into a bucket in a low dosage and have the Neptune ATO refill as the ATO water?
The bags of PHARMA KALKWASSER are sold per pound, and the dosing instructions are by volume (teaspoons.) Can you give us an idea of how many teaspoons are in each bag?
The 2-pound bag will contain just under 9 cups of kalkwasser which would be about 141 teaspoons per 2lb bag or 282 teaspoons per 4-pound bag, but this powder can be compacted so the actual number may differ based on how you measure it. Have a great day!