Are there specific numbers for balanced alk and cal?

[Miller535]

I am still fine tuning my dosing. I was under the assumption that I could just chose whatever cal and alk number I want (say 9dkh and 420ppm cal). But if I use the reef calculator it tells me for this scenario that for a DKH of 9, balanced calcium is 425. Can someone explain this to me please? Does this mean if I want a dkh of 9 my system will be out of balance with a calcium different then 425?

I am mostly using Kalk to maintain, but am also dosing a small amount of 2 part.

 

[Miller535]

@Randy Holmes-Farley?

 

[Nano sapiens]

In practice, having a bit more of one in relation to the other is not a concern for a typical reef aquarium. Just don't get too wild (need to stay within the normal accepted ranges).

 

[Miller535]

In practice, having a bit more of one in relation to the other is not a concern for a typical reef aquarium. Just don't get too wild (need to stay within the normal accepted ranges).

Right now I have been shooting for 8.5dkh and 420 calcium. Figuring this gives me some wiggle room either way. I have mostly LPS and a few softies. But I do also have two small Montis.

 

[Nano sapiens]

Right now I have been shooting for 8.5dkh and 420 calcium. Figuring this gives me some wiggle room either way. I have mostly LPS and a few softies. But I do also have two small Montis.

You'll be fine with that. Alkalinity changes most quickly and is the one to watch in order to keep a consistent level (some check this daily). Calcium tends to rise, or fall, more slowly as there is more calcium that alkalinity in seawater. Magnesium tends to fall more slowly than calcium (if both are not dosed).

 

[Randy Holmes-Farley Verified Community Expert]

In my writings, and in at least one popular online calculator, balance has a very specific meaning, and that meaning should never be thought of as desirable target levels.

That meaning is natural seawater values (about 420 ppm calcium and a bit under 7 dKH) plus or minus calcium and alkalinity in the ratio present in calcium carbonate (18-20 ppm calcium for each 1 meq/l (2.8 dKH) of alkalinity).

Thus, any balanced solution stays balanced and can attain NSW values just by allowing consumption by coral calcification, or addition with a balanced method like a CaCO3/CO2 reactor or balanced two part.