Manual Dosing to adjust Mag Alk Cal… question???

So I have been skipping on water changes a bit or just fewer overall.
I really hadn’t been testing as things were looking good.
Just started getting some algae and some odd coral closures….so tested Tuesday morning.

Oh boy: Alk 6.9, Calcium 320, Magnesium 1260.

So I used the BRS calculator to determine the amounts needed to adjust.
I know I couldn’t get to 9.0, 450, 1350 in one shot. So I dosed a little of all 3 Tuesday morning and evening.
Wednesday after work I dosed some more towards those numbers. And today around dinner time.
Just tested. ALK went a little higher than expected 9.5.
Calcium barely moved to 340.

BUT!!!!!! magnesium took a huge dive and dropped to 950.

I just does a few hundred ml of liquid BRS magnesium.
Oh and my salinity was a little off at 1.024, usually 1.025-1.026, so added a few scoops of 1.020 water to increase the water level above the ato line so it will slowly increase as water evaporates.
Will check in the morning.

I did know that all 3 interact and by raising calcium and Alk the magnesium could drop.
Like I said… will check in the morning.

Good times!!!

Has anyone experienced this???

What mag test kit are you using ? That's an insane drop off and no way your tank consumed that much. The levels of calcium/alk would not effect the mag that drastically.

Maybe grab a second mag test kit ?

I tried multiple salfiert tests which I have been using as my primary test method for years.

I have read if you raise the other 2 it could reduce the Magnesium along the way.

A little better this morning….
Added a little more magnesium sulfate and then some calcium chloride.

Will just keep slowly adjusting and adding as needed.

Just checked now and heading in the right direction!

Problems like this are why I LOVE my All4Reef.

Also, my chemistry guru, Randy Holmes-Farley, recommends not bothering to test Magnesium. He says test results are too problematic to be of any use. Have any interest in a cheap Hanna Magnesium Checker?

I also read his latest posts regarding mag and now our hobby grade test kits are not great at resting for it and we could be having false lows and false highs

radiata said:

Problems like this are why I LOVE my All4Reef.

Also, my chemistry guru, Randy Holmes-Farley, recommends not bothering to test Magnesium. He says test results are too problematic to be of any use. Have any interest in a cheap Hanna Magnesium Checker?

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i have all for reef, but cant just start using it when things are so far outta whack.
Its more to keep things in check once aligned.