Magnesium levels and inhabitants

[Alaska-reefer]

Hi all. Newer reefer here. I was just wondering what level (PPM) of magnesium is too high for cuc?

 

[Ron Reefman]

Mg in the ocean runs around 1300. Many reefers have fought a nuisance algae called Bryopsis by running Mg levels as high as 2000 without doing any damage to livestock.

 

[redeyejedi]

Mine has been over 1500 for years with no issues

 

[Randy Holmes-Farley Verified Community Expert]

It would be a lot simpler if you told us your level, rather than asking a question which is not going to have a perfect answer: what is the maximum amount that is OK.

The only clear issues I've seen reports of at normally attained levels in reef aquaria is that snails become sluggish at elevated levels, say 1600-1800+ ppm.

 

[Alaska-reefer]

Thanks for the responses. I currently am running mg at 1380 ppm. I just noticed that the colors of my LPS corals are brighter at 1380 than when I've had it 1280 ppm.
Like I said, I'm new to reef/salt water and I'm just trying to get the basics down without killing anything.

 

[Randy Holmes-Farley Verified Community Expert]

Thanks for the responses. I currently am running mg at 1380 ppm. I just noticed that the colors of my LPS corals are brighter at 1380 than when I've had it 1280 ppm.
Like I said, I'm new to reef/salt water and I'm just trying to get the basics down without killing anything.

That level of magnesium is not an issue for color or anything else.

I think the observation on color between 1380 and 1280 ppm magnesium (matching NSW at 35 ppt) is likely coincidence.