Low alkalinity

[boxerzz]

My calcium is always at ~500ppm but my alkalinity has infact gone down from 7.5 to less than 7 dkh even though I am dosing kalwasser daily. Why is this so ? I want to raise the alkalinity but it seems to go down instead,

 

[frank2926]

it is because your calcium is to high. You need a balance. What is your magnesium at??? Magnesium is the basis that helps keep calcium and ALk stable. Are you dosing 2 part? if so stop dosing the calcium and just use the ALK till they balance out. If not I would look at your mag levels and the salt you are using.

 

[kfisc]

Great reading below-

http://archive.reefcentral.com/forums/showthread.php?s=&threadid=102605

 

[Randy Holmes-Farley]

You may just not be adding enough to meet the demand.

How much limewater are you dosing to the tank?

How do you make it?

What's in the tank?

 

[boxerz]

everyday I top up my water with pre mixed kalwasser solution. The top up added with 1 teaspoon of kalwasser twice a week ( I only add solution and not the residue). Currently there are octo coral, bubble, torch, cynarina, 3 clams, gonio and some soft corals.

 

[stingythingy45]

^^^

Topping off with kalk is probably just meeting the tank demand.
You seriously need to dose some Alk suppliment or you're going to have some serious problems.I does kalk also,but it's more to maintain what's already there as far as Alk parameters.
You need to get that Alk up either with some baking soda mixture(Randy's part 2) or a purchased product.And dont do it all at one either,you'll have to SLOWLY raise that Alk up.

 

[Randy Holmes-Farley]

Maybe use the limewater to replace all evaporation every day (I do). Adjust the lime in the limewater to meet the demand (up to about 2 level teaspoons per gallon of top off) and add it very slowly (dripping).

 

[boxerz]

limewater only increases alkalinity but not calcium ? Also are there any limewater products ? Actually what I meant was I top up everyday using kalwasser solution. But I make new solution twice a week.

 

[Randy Holmes-Farley]

limewater only increases alkalinity but not calcium ?

No, that is not the point. It boosts both proportionally. If you added nothing at all, alkalinity would drop and calcium wouldn't appreciably drop. That is because there is a huge reservoir of calcium in seawater.

Start at NSW levels of 420 ppm calcium and 2.5 meq/L (7 dKH) of alkalinity. Let corals use calcium and alkalinity down to 1.8 meq/L (5 dKH; they can rarely drop it lower before they no longer can take it up). The calcium drop is only to 406 ppm.

So when alkalinity is low and calcium is OK, that is what you find when you underdose BOTH calcium and alkalinity.

Likewise, if you use limewater to boost the alkalinity from 5 to 7 dKH, calcium will only rise by 14 ppm.


Also are there any limewater products ?

Not sure what you mean. Mrs. Wages Pickling Lime is a commercial brand in the US. I'm not sure what you may have locally. There are hobby brands as well.

 

[sjmckean]

Check your Magnesium. It should be between 1300 and 1500. Proper Magnesium levels will keep high levels of Calcium from precipitating and help keep Alkalinity in balance with the Calcium.