Sudden high Mg?

[bonefish]

For the last few weeks: pH8.2; dKH 8.8-9.8; Ca 460-480; Mg 1360-1400. Tank is just over 6mos old. 8 small LPS frags. Dosing 5mL@/d ESV 2-part for a couple months. Last readings 4d ago.

Tested tonight: pH 8.0; dKH 8.5; Ca 480; Mg 1520.

All a bit off of range I've been seeing. Not that worried, but don't understand the Mg spike, if its real. Using Red Sea test kit, and despite extensive rinsing in tapwater and a final rinse in RODI I see some precipitate in the vial I use for the Mg test (same one every time). Don't know if this is throwing the Mg reading off? Will test again tomorrow.

Otherwise, I took the top off the Biocube 32 4d ago and added AI prime lighting. Don't know if this is related to the change in #s at all.

Any ideas?

Thanks

 

[Randy Holmes-Farley Verified Community Expert]

I don’t think it is real unless you got there by water change. Magnesium test error is very common.

 

[bonefish]

Thanks Randy! Wondering if everyone sees the precipitate that hangs tenaciously on the vial that the Red Sea Mg++ test is done in?

 

[cmcoker]

I can't say the precipitate is the issue. I dont seem to have a problem with the red sea kit, I store my vials in vinegar, rinse thoroughly with rodi before use.
Maybe try a vinegar soak and see if it makes a difference