Magnesium not rising

[AD87]

First time every using Kent Tech M I have added about half of the 16 fl oz bottle over the past few days. It has only increased my Mag from 1050 to 1200. Is this normal seems like alot to suppliment?

Total water volume is 60 gallons. Cal 420 Alk 8.5 (currently increasing).

[bnumair]

mag need increasing by the tons lol. in my 300 gal system few days back to increase from 1200 to 1350 i had to use 227 teaspoons of seachem mag.
go to kents website or any other reef calculator and plug in the numbers and see exactly how much u need to be dosing to increase. also mag should not be increase more than 100ppm per day.

[bnumair]

kents website says 1ml(1/4tsp) will increase 18ppm
1ml=0.03oz
8oz will be 236ml
and from that 236x18=4248ppm
so something is not right here but i do know its take a lot to increase mag.

[bnumair]

http://reef.diesyst.com/chemcalc/chemcalc.html
this also states to dose 16.4oz to go from 1050 to 1200. not sure whats happening here. maybe someone else may have a better idea

[downbeach]

A few questions:
What is your salinity? What are you using to measure it? Is it calibrated? What salt mix are you using?

[AD87]

salinity is 1.026, calibrated refractometer. Reef crystals.

Bnumair I used that calc and it just seems 16 oz is alot to add.

I am also using a salifert mag test kit.

[downbeach]

The Mg in RC should be about 1350 @ 1.026. Have you checked your make up water? It might be worthwhile to double check your Mg test with another kit, or have another reefer friend check it.

[disc1]

kents website says 1ml(1/4tsp) will increase 18ppm
1ml=0.03oz
8oz will be 236ml
and from that 236x18=4248ppm
so something is not right here but i do know its take a lot to increase mag.

That's per gallon. So in his 60 gallon total volume, one ml raises mag by 0.3ppm. By that math, to get the 150ppm bump the OP is looking for it should take (150 / 0.3 = ) 500ml.

[disc1]

Converting back to fl oz.

At 0.03ml per 1oz, that makes it:

500 * 0.03 =

15 oz of Tech M to raise that tank by 150ppm. If it's a 16 oz bottle, then think in terms of 160ppm per bottle for that tank.

[disc1]

Oh no. The first post didn't post. Let me (re) paraphrase.

In the OP's 60 gallons there's a good three quarters of a pound of magnesium if it was all turned back into metal. That's a lot.

In terms of hexahydrate magnesium chloride and magnesium sulfate like we dose into our tanks, that's a little more than six pounds of magnesium salts needed to make the seawater.

There is a lot of magnesium in seawater and when we supplement it we are trying to make big concentration changes with salts that are moderately soluble. You can only make a mag chloride / sulfate solution so strong.

So it is sometimes surprising to people how much magnesium supplement it takes to make a real change in magnesium concentration.

[AD87]

Thanks guys just didnt realize i needed to dose that much. Makes me feel like a noob asking these questions.