Magnesium not dropping

[dodgy67]

I raised my mag levels about two months ago in both my tanks (a 60gall and 20gall) to just over 1600 to help combat some algae problems using Magnesium Chloride Hexahydrate and Epsom Salts, both tanks are now joined together corals are thriving, 10 large clumps of Halimda, I dose Kalkwasser using a ph meter and Bicarbonate of Soda to maintain Ca and Alk..

Mag is still testing over 1600, any ideas why this is not depleting over this two month time period

Tank 1 60gall
Tank 2 25gall
Sump 25gall
ph 8.4 - 8.5
Alk 10-11
Salinity 1.025
Nitrate 0.0
Phosphate 0.02

 

[Sk8r]

Oceanic salt, eg, has a very high mg content. Take a look at your salt mix and see if it's just naturally high: if nothing is using it up and you're continuing to do water changes with high mg salt, it can be real hard to change. I switched to Instant Ocean because of this problem.

 

[dodgy67]

Magnesium not dropping

Sk8r not done a water change in two months only a small top up due to salt creep loss when sal dropped to 1.023

 

[bertoni]

Magnesium often is consumed in very small amounts. My tanks never required magnesium supplementation due to consumption, although they ran for more than 10 years. 1600 ppm probably is safe enough, but you probably would need to do water changes with a lower-magnesium product to drop the level in any reasonable time frame.

 

[tmann51]

Un readable magnesium levels

Un readable magnesium levels

A few months ago I checked my magnesium levels and found them to be low. I started adding BRS mag for two part dosing and monitoring the levels. I'd been using Salifert test that was not expired. I switched to Red Sea magnesium test and discovered my adjusted levels to be off the scale, over 1600! All my water pumps are regularly locking up and my Osmolator also malfunction. I'm also having to dose large amounts of calcium and alkalinity daily. 20 percent water changes weekly have not moved to readable levels. Any help would be appreciated. I'm using Red Sea Pro salt currently.

 

[bertoni]

You probably can get a reading by using two syringes for the final titration, and adding the results. I'd increase the water change rate, if that's not too much work or cost. To cause that kind of problem, I'd expect the magnesium to be extremely high. What is the magnesium level in the freshly-mixed saltwater?