Magnesium dropping rapidly

[Chris918]

Hello,

I'm using Coral Pro Salt in a tank designed to grow out SPS frags. I'm using Red Sea's Reef Care Recipe and try and aim for the parameters listed on the bucket. I tested four days ago as instructed and kept my salinity stable to try and determine how much I need to dose each day. Here were the changes:

Calcium: 450 to 440 ppm
Alkalinity: 11.8 dKH to 10 .7 dKH
Magnesium: 1350 ppm to 1290 ppm

I'm not surprised by the first two tests, but I'm shocked at how quickly Magnesium drops in this system. Does anyone have any ideas why this may be happening? To my understanding, Magnesium is normally only dosed 1-2 ml per day per 25 gallons.

Thank you for any help

 

[mcgyvr]

How many times have you tested mag consumption?
Don't react on one reading.. Could be testing error or whatever..

 

[bertoni]

That does seem rather high. There's testing limitations at play, though, and water changes can skew the results, too. I would wait for more testing results to see what's happening. 1290 ppm is fine for magnesium.