Reef Discussion

[potatocouch]

I feel that my Mg depletion rate is high.
Alk depletion rate is probably at normal size.
Ca depletion rate is fairly low and can usually be replenished by weekly WC.

So .......now I'm confused about is my Mg depletion ....

Please refer to the following stats for reference:

As some already know, I have ~ 55 gallons (~ 180L) tank (CADE) and dose using Red Sea foundation A, B and C.

I've calculated the dosing (based on 180L water columns) and its impact to my tank:

• 20 ml of C will raise 11 Mg.
• 5 ml of B will raise 0.3 kH.
• 20 ml of A will raise 22 Ca.

If you look at the Mg columns above:

• Weekly WC was done on 26/02/2016, which brings Mg level to 1300.
• Then test was done on 28/02/2016, reading on Mg was 1260.
• 20 ml dose was then done on 28/02/2016.
• 40 ml dose was then done on 29/02/2016.
• 20 ml dose was then done on 1/03/2016 morning.
• Test was done on 1/03/2016 evening, reading on Mg was 1320.
• Test was done the next day (2/03/2016) afternoon, reading on Mg was 1270.
• That is a drop of 50 ppm of Mg in just 1 day.

It doesn't sound right, does it? especially when the tank doesn't have clam and only has 1x torch, 1x goniopora, 2x hammers, colony of zoanthids (I just added few more frags), colony of turbo snails, 1x anemone and 4 fish.

Any input/s are much appreciated.

I'm a tad confuse about what is my Mg depletion rate and how much exactly should I dose for Mg.

For Alk, I think 5 ml per day is the right amount to keep kH at 8.3 ~ 8.5.
For Ca, weekly WC should replenish it to the right amount at 420.

Charting provided as reference:

 

[slin1977]

What level is your Mg of your WC?
What brand of salt are you using ?

 

[potatocouch]

What level is your Mg of your WC?
What brand of salt are you using ?

 

[slin1977]

What test kit are you using for Mg?

 

[potatocouch]

What test kit are you using for Mg?

Salifert expiry 2020

 

[potatocouch]

Anyone know what the range means? i.e. Mg 1250 - 1310 ... means between?

So for 1.026 SG, Red Sea predicts the Mg level to be at the range between 1250 to 1310 mg/L?

I just test my newly mix ASW (at 1.026 & 26c) and it measures 1200 mg/L.

 

[potatocouch]

@slin1977 @ezza i know at one stage in your reefing career, you had the opportunity at using the Red Sea Coral Pro ...

And it seems that you guys had positive response to it.

The thing I don't get with Red Sea pro, isn't the level of Alk (12.3 - 12.7 dKH) too high? or maybe not?

 

[slin1977]

I liked coral pro and had success using it , although my tank parameters alkalinity was between 5.5 and 8 kh.
The coral pro water changes were a lot higher in alk.
I had a clam and fast growing SPS so the demand for alkalinity was high.