New to 2 part. Quick question

whyoming.white · Nov 17, 2018

System info
120gal display
30 gal sump

Total volume roughly 130 gal

Sps tank

I was using kalk in my top off for a long time i am now moving to 2 pArt but the recommended dosage seems high for calcium

when I tested yesterday I got these results

Alk-9.7
Cal-440
Mag-1380

Today
Alk-9.2
Cal-425

I only added rodi to top off so I could track usage over 24hr period.

According to the BRS calculator to get back to the levels i mentioned yesterday I would need to dose the following. The calcium number is the one that seems super high.

ALK- 46.4ML
CAL-399.1ML

I am using BRS bulk soda ash(old style jug) and BRS bulk calcium chloride(old style jug) for my calcium

Do those numbers seem off to anyone?

NY_Caveman · Nov 17, 2018

I am new to this, but my understanding is you want to be dosing equal amounts of two part. If there is a discrepancy in the balance you need to correct that first.

The balance of 9.7 dKH Alkalinity would be 429 ppm of Calcium. 9.2 dKH is 426 ppm. It would seem, with the results from a hobby test kit, you are in line with that.

For me, since I feel Alkalinity is crucial, I set that level and then match Calcium to equal it. An exact Calcium level is less crucial and harder to test.

Randy Holmes-Farley · Nov 18, 2018

One days measurements will be way too noisy to determine exact dosing values, especially for calcium.

That said, the value you are getting for calcium dosing seems about 2x too high. There are two of my recipes that BRS uses,a nd the one with sodium carbonate (soda ash) is twice as potent for each part as the one with sodium bicarbonate (baking soda).

perhaps you are confusing the two, or perhaps you really made the calcium part extra dilute.

Can you describe exactly what you added to make the calcium solution? (how much solid, how much water).

My recipe #1 (uses sodium carbonate) needs 200 mL of the calcium part to boost 130 gallons by 15 ppm.

This is the calculator I recommend:

http://reef.diesyst.com/chemcalc/chemcalc.html