Mag Issues

Terry4505 · Nov 25, 2014

I am having a difficult time keeping Mag up. I use a dosing pump for the Big 3 and my current levels are:

Cal- 480 (Red Sea)
Alk- 10.1 (Hanna)
Mag- 1280 (Salifert)

after adding 40 or so mls of Mag over the last few days. I had the Mag up to 1380 on Saturday when I tested last, but has dropped again.

Any idea what is causing the drop? And is it ok to dose as much as necessary to keep it up?

150 gallons twv, mixed reef with mostly SPS.

Phosphate .03 (Hanna)
Nitrate 0 (API)

Eckolancer · Nov 25, 2014

Is the tank newer? Also are you seeing coralline showing up more? If so could be normal till everything stabilizes and is covered in coralline.

Randy Holmes-Farley · Nov 25, 2014

If you are suggesting that magnesium dropped from 1380 ppm to 1280 ppm in 3 days, then that can only be due to a testing error (which is common) or to a big water change with a low magnesium mix.

Magnesium depletion rates are more like 0.1 to 1 ppm per day.

I'd stop dosing any magnesium, or dose a low steady amount, and just track it for a few weeks.

Terry4505 · Nov 25, 2014

Thanks for the replies.

I retested with Salifert kit and it came out at 1350. I am using a Jebao DP-4 doser for Alk, Cal and Mag. I have it dosing 1ml per day for now. I will leave it an retest in a week and see where we're at.