PDA

View Full Version : Rift Lake Buffer Jeff D***


Kodiak
March 4th 04, 03:05 AM
Hi Jeff,
Previous post you mention;

MgCl2-6H2O 0.2 g/L (Magnesium Chloride or road de-icer)
NaHCO3 0.25 g/L (Sodium Bicarbonate baking soda)
KHCO3 0.125 g/L (Potassium Bicarbonate)
CaSO4-2H2O 0.035 g/L (Calcium Sulfate Gypsum)

This adds 8 mg/L Ca++, 69 mg/L Na+, 24 mg/L Mg++, 34 mg/L K+, 258 mg/L
HCO3-, 70 mg/L Cl-, & 20 mg/L SO4-.

Can you recheck "K" ? I did the math and get 48 using your recipe.
Here is how I did it;

0.125g/L of KHCO3 = 125ppm
Molecular weight of K is 39.01
Formula weight for KHCO3 is 100.1

125 x 39/100.1 = 48ppm of K or 48mg/L, not 34mg/L.
Can you please recheck. All other numbers I checked OK.

I imagine the extra bit of K you get from your recipe 48,
as opposed to the ideal for tanganyika 34.2 is also no big deal.

The HC03 at 257 seems a little below ideal of 344.
Can you comment?

....Kodiak

Jeff Dantzler
March 4th 04, 06:34 PM
Kodiak > wrote:

> MgCl2-6H2O 0.2 g/L (Magnesium Chloride or road de-icer)
> NaHCO3 0.25 g/L (Sodium Bicarbonate baking soda)
> KHCO3 0.125 g/L (Potassium Bicarbonate)
> CaSO4-2H2O 0.035 g/L (Calcium Sulfate Gypsum)

> This adds 8 mg/L Ca++, 69 mg/L Na+, 24 mg/L Mg++, 34 mg/L K+, 258 mg/L
> HCO3-, 70 mg/L Cl-, & 20 mg/L SO4-.

> Can you recheck "K" ? I did the math and get 48 using your recipe.
> Here is how I did it;

> 0.125g/L of KHCO3 = 125ppm
> Molecular weight of K is 39.01
> Formula weight for KHCO3 is 100.1

> 125 x 39/100.1 = 48ppm of K or 48mg/L, not 34mg/L.
> Can you please recheck. All other numbers I checked OK.

You are right. I must have a mistake in my original spreadsheet
calculations or misread a number when typing it out.

> I imagine the extra bit of K you get from your recipe 48,
> as opposed to the ideal for tanganyika 34.2 is also no big deal.

I was trying to get as much HCO3- as possible, without adding too
much Na+.

> The HC03 at 257 seems a little below ideal of 344.
> Can you comment?

257 is lower than 344 for sure. To get to 344, the concentration(s)
of Na+ &/or K+ would be very high. In the lake, you have millions of
tons of CaCO3 in contact with the water slowly dissolving. That's why
the Ca++, HCO3- (formed from the CO3--), and pH are so high. It is hard
to achieve that in a fishtank. CaCO3 is not very soluble.

I found that the amount of bicarb I added (as NaHCO3 & KHCO3) along
with a coral sand (mostly CaCO3) substrate was enough to get my pH
up to about 8. I was happy with that.

Hope this helps.

Jeff Dantzler