low alk (6dkh) and calcium 400ppm ???????

[littlesilvermax]

Originally Posted by Aleks

Ahh, ok so what I was thinking was correct, that a balanced increase in both is what will correct the problem... up it to ~450 calcium and around 9 dkh....

That is about right. I personally only target about 430 for calcium and between 7 & 10 for dkh. (always nice to have it higher then NSW in case something happens)

Don't forget that unless magnesium id where it should be (above 1300 ppm) you won't get those numbers, as magnesium helps hold calcium in suspension.

[Myka]

For an explanation on how calcium, alkalinity, and magnesium interact with each other take a read through the link in my signature. I also suggest different products, and dosing methods.

Balanced Calcium and Alkalinity:

1.4 dKH to 350 ppm
2.1 dKH to 375 ppm
5.6 dKH to 400 ppm
9.1 dKH to 425 ppm
12.6 dKH to 450 ppm
16.1 dKH to 475 ppm

Personally, I aim for 9 dKH alkalinity and 420 ppm calcium. Generally, natural seawater contains 7 dKH alkalinity and 410 ppm calcium, so you can't go wrong imitating that either.

[Aleks]

Originally Posted by littlesilvermax

That is about right. I personally only target about 430 for calcium and between 7 & 10 for dkh. (always nice to have it higher then NSW in case something happens)

Don't forget that unless magnesium id where it should be (above 1300 ppm) you won't get those numbers, as magnesium helps hold calcium in suspension.

RGR, and I assume I have low Mg due to my salt mix......

[littlesilvermax]

Originally Posted by Aleks

RGR, and I assume I have low Mg due to my salt mix......

What salt?

[Aleks]

Originally Posted by littlesilvermax

What salt?

Instant Ocean, reported to be 1070 out of box......Mg tests are expensive so I've neglected to test this one thing...

[Myka]

Magnesium plays a pretty important role, it's worth the cost of the kit.

[Aleks]

Originally Posted by Myka

Magnesium plays a pretty important role, it's worth the cost of the kit.

I don't disagree at all....its just there's 2 schools of thought right? Those that test and dose everything, and those that don't over analyze and just do WC's and have no problems at all blissfilly unaware....I'm not sure which I'm following yet (low maintenance is key)....now that there was a reply about natural seawater being 410/7dkh I'm not as worried about it, because I'm in the norm :-) still would be nice to know what it is for the sake of knowing.....

I really didn't mean to pull this thread off its original track so please back to calcium/hardness :-)

[Myka]

Originally Posted by Aleks

I really didn't mean to pull this thread off its original track so please back to calcium/hardness :-)

A thread goes where it goes, that's why it's called a disucssion board. A discussion about calcium and alkalinity without magnesium is like discussing water and earth, but not air.