Dropping dkh but not cal

[Miller535]

Hello, I have a 125 gallon fowler tank that has been running for a out 6 years. I recently started paying attention to alk and cal because I want to convert to a reef. I am dropping .5 dkh a day but my calcium level never moves. I thought they were tied together. Is something wrong? I know my dkh measurements are accurate as I have been doing it both with hanna checket and red sea alk test.

 

[Miller535]

And if I keep doing sodium bicarbonate (brs) each day to make up for the drop, will it drive the calcium down?

 

[amps]

For every 0.5 dkh drop in All, calcium only drops about 3ppm. That small amount is far too low for most test kits to detect and we'll within their margin of error. What you need to do is continue your dosing regimen but look for changes over a two week period. That will give you a more accurate picture as to what the tank is consuming without the granular errors that come with testing every day.

 

[Miller535]

Thank you. I want to get a handle on alk and cal before I buy any corals.

 

[Miller535]

@Randy Holmes-Farley should I dose a equal amount of calcium as alk each day because the used amount is so small as amps said?

 

[pdxmonkeyboy]

When you get the cal and alk within range, always dose the same amount.

 

[amps]

It depends on wether or not your supplements are balanced. Some 2-parts are designed to dose equal amounts of each to match their relative consumption. Others are imbalanced and you'll need to test over a longer period of time and do the math to figure out how much of each to add.

I'm not sure about the BRS recipe but I'm sure you can find the info on their site. Look for the keyword 'balanced'.

 

[Miller535]

I'll look at see what their 2 part says

 

[pdxmonkeyboy]

Brs is equal parts, as is the diy recipe. Dont mess with 2 part that isnt 1 to 1 just one more thing to screw up

 

[Sean Duggan]

I would recommend set a dosing regiment using an auto doser and then check it 3-4 days later. See how much the levels have changed and adjust your doser. Repeat until you find an acceptable balance. When I first set up my tank I was dosing brs 2 part and I ended up having to dose way more alk in the beginning. As the tank matured though the calcium and alk balanced off