my Mg never been decrease..

[kamkam1999]

HI everyone, since i moved to the new 3 ft SPS tank 4 months, i have lots of SPS and have kamore CMK to check ca mg kh, however my mg is still in 1380-1420 and i have never dose any about mg, i have dosing KH for 200ml/day CA for 27ml/Day, and CA 450 MG 1400 KH 7.6. why would this happened? please help

i have used Hanna, Aquaforest test kit, salifert test kit, all showed same value

 

[kamkam1999]

i do 5% water changes every week, using aquaforest reef salt+ at 1.026-1.027

 

[Randy Holmes-Farley Verified Community Expert]

Magnesium is super slow to deplete.

 

[kamkam1999]

Magnesium is super slow to deplete.

is it normal? because my frirends' Mg drop really fast

 

[Randy Holmes-Farley Verified Community Expert]

is it normal? because my frirends' Mg drop really fast

Really fast is test error. Magnesium test error is so common that I do not recommend even testing it. I recommend just dosing it based on calcium demand.

Just say NO to magnesium testing: RMM is born

OK, this thread has been many years in the making, and I'm posting it here since folks in the chem forum are probably already tired of all the threads relating to problematic magnesium testing. I'm going to propose a method, let's call it the Randy Magnesium Method, or RMM for short. All good...

www.reef2reef.com

Magnesium never depletes faster than about 1/10th of the calcium depletion rate. Sometimes much slower.

Coralline algae is a big user, and gives that 1/10th rate. Some corals incorporate relative little magneisum and the relative rate is much lower.