Hmm Can't raise Mg...

What's up everyone,
I was doing some tests a few days ago and tested my Mg with a Salifert kit, it was a bit low, around 1100. Cal was 400 and DKH was 9. So obviously I had to raise the Mg. Well here's the thing I can't get it over 1140. Over a period of three days I does Mg and a good amount of it and can't get it over 1140. About the only thing it did was effect my Cal and Alk levels. I guess it could be the test kit gone bad, but it did test at over 1400 a few weeks ago, maybe the MG I'm adding is no good? I'm going to test my Mg (that I'm using to dose) with the kit and some RO/DI later today. any other thoughts?


Thanks!

 

What Mg supplement are you adding? Plus how much?

As long as your not buying something like Kents and just purchasing the mineral it self then it will never go bad, it's an earth element.

 

Hey! Two questions:

1. Is your pH around 8.3?!
2. Is your water getting cloudy when you add Mg?!

 

The supplement is only available up here in Canada, my PH is 8.2 and if anything it may cloud very slightly.

 

Put the spoon away and get the measuring cup at where you are now at 1140 add about 1/2 a cup then test in a few hrs and hot it again according to levels after a real dose . I use simple Epsom Salts have used Mag Chloride never saw any differences expect for the cost. I never brought in the sulfates build up in a saltwater tank hell salt is salt. and most salts lack sulfates anyways .

 

OK thanks Tangster I will give it a shot.

 

yeah noticed that you got to dose a lot. Mine went down too and spoon isn't going to do much. Of course, test before you dose. Good luck

 

Yeah! The trick with Mg is that most supplements are offered as a hydrated salts. For example very common magnesium chloride (MgCl[sub]2[/sub]) is sold as a hexahydrate: (MgCl[sub]2[/sub] 6H[sub]2[/sub]O). Consequently, 53% of dry supplement powder is actually water trapped in crystalline state! Seachem, for example sells Mg supplements as sulfate salts, that intrinsically contain less water. The more crystalline water, the lower residual concentration of Mg in one tablespoon of given supplement! In other words, depending on the manufacturer of supplement the same 5ppm increase in Mg level will require different amounts of powder! In one case it will be e.g. 1 tea spoon per 20 gal in other this might even be 3 spoons! The moral of this story is: try before you buy !

 

a little pointer, I went through the same thing and there's a handy calculator to figure out how much Epsom salt (or anything else for that matter) to dose in your tank, and remember!! Don't increase more than 100ppm a day!!! Good luck!!!