Foundation elements dropping... now what

[Jason boles]

so I’m super excited that I am finally seeing a drop in calcium, magnesium and alkalinity.

This is what I’m working with.

I have filled up my tank in the last couple of weeks with frags, and have been testing all nightly at 10, and all weekly.

I use Red Sea Coral Pro salt. Before yesterday my test read

Ca 425
Mg 1400
Alk 10.25

I do a 3/4 gallon water change twice weekly, Sunday and Wednesday. I turkey bast the rockwork and sandbed daily, turning all live sand. I also clean the rear chambers / pump monthly.

I water changed yesterday and only tested my alk which was 10.5, and today it was 9.8. Last night was at 1045 and tonight was at 10.

Ca 375
Alk 9.8
Mg 1300

So this is obviously a drop from the bucket mix.

That leads me to the fact that I just purchased an ato because I plan on dosing Kalk... I purchased bright wells Kalk +2 with my ATO and have not used it as of yet.

So should I just add a small amount to my ATO water and keep testing until my levels stabilize???

All help and advice is appreciated, and questions are welcomed.

 

[Jason boles]

Oh. I also micro bubble every night

 

[Jason boles]

Guess I’ll give the Kalk a whirl and see how it goes.

 

[chipmunkofdoom2]

I personally would not attribute the drop to the water change. Testing error probably is playing a part in the results you're seeing.

At S = 35 ppt, RSCP should have alkalinity = 11 - 12 dKh, Ca = 450 ppm and Mg = 1,420 ppm. If doing a water change dropped your parameters, it would have to be lower than the levels you're reading now. If alkalinity went from 10.25 dKh to 9.8 dKh, the salt mix would have had to be below 9.8 dKh. The calcium would have had to be below 375 ppm, and the Mg would have had to have been below 1,300. Not impossible, but unlikely for Red Sea Coral Pro.

Also, your water changes are about 6%. It would be mathematically impossible for dilution alone to drop your calcium from 425 to 375. Even if the newly mixed saltwater had no calcium at all, your calcium level would be around 400 ppm, not 375 ppm.

Do you test your new water before you add it to your tank? Do you only mix 3/4 a gallon at a time? Do you mix up your dry salt mix before adding it to the fresh water?

With regards to dosing calcium hydroxide, many people do this in ATOs. I personally don't like dosing limewater through an ATO though. I prefer to dose it with a dosing pump on a schedule. ATOs are far too imprecise and prone to failure for me to be comfortable dosing something like limewater using one.

 

[Jason boles]

After my ater change my levels where consistent with the salt mix... the drop came the next night. I am attributing the drop to the corals uptake in the tank.

I do test the water after mixing. I mix 5 gallons at a time and use it up, then mix again. It is testing perfectly. I also did give the salt a good mixing when I got it. Not since though. I’ll keep that in mind before next change.

I guess my question is how to use the limewater. Just add a small amount and see if it can keep the Parm s stable? Or do I do a water change to bring them back up and then use the Kalk?

 

[Jason boles]

I reread your response.

Setting aside the fact that I wasn’t thinking the water change dropped the elements...

Are you saying that the numbers are all in accurate due to the ratios being so far off?

 

[chipmunkofdoom2]

No, I did not mean to say that the results are all inaccurate. They are just unexpected. The water change should not have caused that drop, and that's a very large drop to happen overnight, at least with regards to calcium, without any explanation. Testing error is likely at least partially responsible for the overnight drop you observed, especially with regards to calcium and magnesium.

Kalkwasser is not ideal for one-time increases, such as correcting calcium or alkalinity levels, because of the high pH. This is due in part to how dilute limewater is, even at full saturation, but also due in part to how much of a pH boost comes with limewater.

If you wanted to start dosing fully-saturated limewater and see if that can increase your values over time, you could do that. You may need a two-part to correct the imbalance though.

 

[Jason boles]

I am thinking the reason for the drop is because the corals used it up and therefore would need to start dosing for what they are using.

Is this insane to think they took up that much??

Here is a pic of my tank. I have a lot of frags!

 

[Randy Holmes-Farley Verified Community Expert]

so I’m super excited that I am finally seeing a drop in calcium, magnesium and alkalinity.

This is what I’m working with.

I have filled up my tank in the last couple of weeks with frags, and have been testing all nightly at 10, and all weekly.

I use Red Sea Coral Pro salt. Before yesterday my test read

Ca 425
Mg 1400
Alk 10.25

Ca 375
Alk 9.8
Mg 1300

So this is obviously a drop from the bucket mix.

.

That magnesium drop is not due to consumption. It is most likey testing error, or a big drop in salinity. Real magnesium consumption is about 1/10th of the calcium drop, and is typically not more than 1-2 ppm per day max.

 

[Randy Holmes-Farley Verified Community Expert]

If you added no additives, and the alk dropped by 0.5 dKH (which is perfectly reasonably and low demand), the real calcium drop was about 3-4 ppm and the magnesium drop was well below 1 ppm.

 

[Jason boles]

I did find my salinity was a bit off.

Does testing time effect results, or can I test at any time in the day?

Should I just concentrate on dKH and move from there?

I feel lost as this is my first go round.

 

[Jason boles]

I did a .75 g water change and brought my salinity back up. It was 1.24.

My testing results didn’t seem all that accurate, so I got Salifert test kits today to compare.

Honestly they look exactly the same as the Red Sea (haven’t used it yet)