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Brightwell Aquatics Kalk+2 is a premium 450g powder supplement delivering calcium, strontium, and magnesium in natural aragonite ratios to support healthy reef-building invertebrates. It stabilizes pH and alkalinity without adding chloride, ensuring a balanced marine environment. Made in the USA, this scientifically backed formula is designed for serious reef hobbyists seeking superior aquarium care.




| ASIN | B00BUFTC5S |
| ASIN | B00BUFTC5S |
| Allergen Information | Sulphites Free |
| Best Sellers Rank | #38,740 in Pet Supplies ( See Top 100 in Pet Supplies ) #374 in Aquarium Water Treatments |
| Brand Name | Brightwell Aquatics |
| Customer Reviews | 4.6 4.6 out of 5 stars (237) |
| Date First Available | April 9, 2013 |
| Global Trade Identification Number | 00810086011155 |
| Included Components | Kalk+2 |
| Item Form | Powder |
| Item Type Name | WATER CONDITIONER |
| Item Weight | 16 ounces |
| Item model number | KALK450 |
| Liquid Volume | 1 Gallons |
| Manufacturer | TopDawg Pet Supply |
| Manufacturer | TopDawg Pet Supply |
| Manufacturer Part Number | KALK450 |
| Model Number | KALK450 |
| Product Dimensions | 1 x 1 x 1 inches; 1 Pounds |
| Target Species | Invertebrates |
| UPC | 810086011155 |
| Unit Count | 1 Count |
T**N
Works Perfectly Just Be Careful With Amount Used
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.
N**S
Works great.
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.
S**L
Does the job
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!
F**K
Go easy on it!
The bag is crap but the product is great. Coraline in a new aquarium after just a few months. Dont overdose!
9**E
Great Stuff
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.
A**R
A great solution I came up with that will help reduce ...
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.
N**N
Great price on a great product.
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.
C**T
Know your customer better.
My magnesium keeps running low. This product states that it has the same levels of Magnesium and Strontium as found in some kind of Rock they name. Don't care about the rock care about if it has the right rations for top off water. Obviously there a a ton of variables but wish they would just mix it so that it is correct for reef tanks and say that vs just grinding up a rock with the proper elements. Something like this product produces the three elements in the correct rations for Sea Water vs a rock that we grind up.
F**I
Prodotto valido, coniuga i vantaggi della Kalkwasser con quelli del Magnesio e dello Stronzio per un ottimo effetto stabilizzante sul KH e l'alcalinità nell'acquario di barriera.
Trustpilot
2 weeks ago
2 weeks ago