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Brightwell Aquatics

Brightwell Aquatics Kalk+2 – Premium Kalkwasser Powder Supplement with Calcium, Strontium, and Magnesium for Reef Aquariums, pH & Alkalinity Support, 1.8KG

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Availability: In Stock.
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Size: 1.8-kg


Features

  • ESSENTIAL CALCIUM, STRONTIUM & MAGNESIUM: Brightwell Aquatics Kalk+2 provides the necessary calcium, strontium, and magnesium in the same ratios found in aragonite, supporting healthy reef-building invertebrates like corals, clams, and calcareous algae.
  • MAINTAINS pH & ALKALINITY: Brightwell Aquatics Kalk+2 helps maintain a stable pH within the optimal range while temporarily supporting alkalinity levels, promoting a balanced and thriving reef environment.
  • NO CHLORIDE ADDED: Unlike other calcium supplements, Brightwell Aquatics Kalk+2 does not contain chloride or any other conservative elements, making it a safer choice for hobbyists who want to avoid additional salts in their aquarium.
  • PROVEN FORMULA FOR REEF KEEPERS: Brightwell Aquatics Kalk+2 improves upon traditional calcium supplement formulas, offering a more effective and scientifically-backed solution for aquarium hobbyists.
  • AMERICAN-MADE EXCELLENCE Brightwell Aquatics is an industry-leading brand committed to providing innovative and scientifically backed aquatic care products. Made in the USA, we consistently deliver advanced superior quality solutions to elevate the vibrancy and health of your aquarium.

Description

Brightwell Aquatics Kalk+2 is an advanced Kalkwasser-based powdered supplement designed to provide essential calcium, strontium, and magnesium for reef aquariums. These elements are crucial for the formation of aragonite, the skeletal material of reef-building invertebrates like corals, clams, and calcareous algae. Unlike traditional calcium supplements, Kalk+2 does not contain chloride salts, making it a safer choice for reef aquariums. It also helps regulate pH and temporary alkalinity, maintaining stable conditions for your marine life. Kalk+2 is formulated by a marine scientist and is ideal for experienced hobbyists who are familiar with kalkwasser products. Brightwell Aquatics Kalk+2 is designed to support the building blocks of coral formation and vibrant reef ecosystems. By supplementing with this product, you can ensure that your reef tank is optimized for the best possible environment for your marine life.

Brand: Brightwell Aquatics


Liquid Volume: 4 Liters


Item Weight: 1.8 Kilograms


Item Form: Powder


Unit Count: 1 Count


Product Dimensions ‏ : ‎ 19 x 11.88 x 6.13 inches; 3.97 Pounds


Item model number ‏ : ‎ KALK1.8KG


Date First Available ‏ : ‎ June 24, 2004


Manufacturer ‏ : ‎ Brightwell Aquatics


Best Sellers Rank: #40,114 in Pet Supplies (See Top 100 in Pet Supplies) #384 in Aquarium Water Treatments


#384 in Aquarium Water Treatments:


Customer Reviews: 4.6 4.6 out of 5 stars (239)


Brand Name: Brightwell Aquatics


Manufacturer: Brightwell Aquatics


UPC: 810086011162


Model Number: KALK1.8KG


Manufacturer Part Number: KALK1.8KG


Unit Count: 1 Count


Item Type Name: WATER CONDITIONER


Included Components: Kalk+2


Liquid Volume: 4 Liters


Item Weight: 1.8 Kilograms


Item Form: Powder


Pet Type: Fish


Target Species: Invertebrates


Allergen Information: Sulphites Free


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Jul 22

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Works Perfectly Just Be Careful With Amount Used
Size: 225-g
I had wanted to bump pH up from 7.9 to 8.3 for over a year because they say you get faster coral growth (BRS did a side-by-side experiment couple months ago out there on YT) but never had much luck breaking 8 with Kents or Seachem products - plus was leery of nuking the tank by accidentally overdosing with homebrewed kalkwasser. Started off using less than recommended Kalk in a big bucket of RODI and didn't touch it for a day to let everything settle. I then carefully did manual top offs from the bucket (stay away from the sediment) over the course of a week and was shocked when the pH came out at 8.4 that weekend (100g system and had planned on slowly raising over 2-3 weeks). That was about 2 months ago, and I've since been able to maintain at 8.3 just as hoped for. Finding that sweet spot in your parameters really does seem to boost SPS growth to the point that you can literally see montis getting bigger every day as opposed to weekly. Highly recommend - but for the love of your tank, use less than you think you need and take it slow. ... show more
Reviewed in the United States on June 13, 2019 by Todd Maniac Wilson
    • Works great.
Size: 450-g
Review Image by Neal Enns
Does what kalk does in a reef tank. Has the extra elements as a bonus which is nice. High quality and clean. Keeps my reef going and my sps happy.
Reviewed in the United States on May 27, 2024 by Neal Enns
    • Great Stuff
Size: 225-g
I had used 2 part in the past and it worked fine. I decided on my new reef to use kalk. Why? A lot of the old-school reefers like it and use it even with 2-part; it bumps up your pH. I was impressed. My corals and coraline algae went crazy! If you can grow coraline, your tank is ready to grow SPS. I mix it in a lemonade canister with about 1/4 cup of vinegar and 1 cup of water; I then added the remaining gallon of water. After 15 minutes the kalk settles and I use the spigot to collect my ato water. ... show more
Reviewed in the United States on December 19, 2018 by 9StickNate
    • Go easy on it!
Size: 1.8-kg
The bag is crap but the product is great. Coraline in a new aquarium after just a few months. Dont overdose!
Reviewed in the United States on December 15, 2019 by Fredrik
    • Does the job
Size: 225-g
Kinda pricy if you have a larger tank, but would be great for a smaller reef. Got this in a bind so I could get it next day and I will say it absolutely works and kept my tank stable . Potent stuff as well . Had to use slightly less then I was using standard kalk with the same results. Big plus on the added mag as well. I would say if you have a smaller or low demand larger tank this will absolutely work! ... show more
Reviewed in the United States on December 22, 2023 by Shanna McMichael
    • A great solution I came up with that will help reduce ...
Size: 450-g
The easiest way to keep ALK and CAL stable. My coral all thrived once I started using the Brigtwell Kalk. Be advised though any kalk will beat up your pumps. I had a few clog up and started dipping them in white vinegar overnight which helps remove the calcium buildup. A great solution I came up with that will help reduce the issue of sediment mucking up your ATO reservoir and tank is I bought a Chemical Guys dirt guard on Amazon. I placed it on the bottom of a 5 gal bucket and use that bucket to store my lime water. The sediment floats to the bottom of the bucket underneath the dirt guard and it helped a lot. ... show more
Reviewed in the United States on May 20, 2017 by Amazon Customer
    • Great price on a great product.
Size: 450-g
If you are familiar with this product, you already know how effective and essential it can be when used properly. Also, you'll quickly notice how much cheaper it is to order from this seller than it is to purchase from a local store. Great value. Excellent price.
Reviewed in the United States on April 12, 2021 by nathan
    • Single handedly saved my reef tank!
Size: 225-g
I dosed this over 6 months while not doing any water changes and neglecting my reef. It kept my reef alive and helped coraline algae to grow, I would guess from the strontium that is added to this kalkwasser formula. After resuming water changes and resuming upkeep of my reef, I have been dosing this regularly with top off water. Corals love it and it maintains my magnesium. I LOVE IT! ... show more
Reviewed in the United States on April 27, 2021 by Kyle

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