Raising Mg

[StirCrazy]

Originally Posted by untamed

In fact, the best way to move it might be to do significant volume water change.

Actualy it might be the worst way salt mixes are almost all low for Mg content. I have tested two popular types now and while they are not overly low they are under 1100 in a fresh mix.

there was a big thing on this a couple years back and it has to do with the cost of the Mg additive and how much is needed.

Johnny Reefer, how are you calculating that you have that much water? like I mentioned befor you have to take off the amount of rock/sane/ect you have or you will be buying way more Mg additive than you will need. I have a 170 gal setup with the tanks, but when I did my calculations on how much Mg attitive I used to how many PPM it went up in my tank it worked out that I only have 95.2 gal of actual water in the system. this is a nice thing to do if for no other reason than to figure out exactly how much water you have for future additions of different attitives. takes the guess work out of the picture.

Steve

[Ruth]

I have just started to switch one of my tanks over to the new Seachem reef salt which is supposed to be higher in Mg. - I will test it next week when I mix up a batch. The other thing I have heard of but have never tried is to run some - I believe it is dolomite - in your calcium reactor to maintain mg.

[Doug]

In past years, before reactors, I always used ESV magnesium with good success. When I started to run a reactor with ARM media, the level was always around 1350ppm.

I dont run a reactor anymore. I now add a magnesium product to any new batch of saltwater. Plus a spoon of calcium, to bring it up to proper levels.

[Johnny Reefer]

Originally Posted by StirCrazy

Johnny Reefer, how are you calculating that you have that much water? like I mentioned befor you have to take off the amount of rock/sane/ect you have or you will be buying way more Mg additive than you will need. I have a 170 gal setup with the tanks, but when I did my calculations on how much Mg attitive I used to how many PPM it went up in my tank it worked out that I only have 95.2 gal of actual water in the system. this is a nice thing to do if for no other reason than to figure out exactly how much water you have for future additions of different attitives. takes the guess work out of the picture.

Steve

The main tank is 180gal and I estimate the sump has 25gal in it. (EDIT: The sump tank size is 33gal, so instead of calling it 213gal gross I call it 205gal net. Ya, I know. Whatever. Sorry for any confusion this may have caused.) I realize that the LR and LS displaces water and that the 205gal isn't a true net amount, it's just that everyone, for the most part, when speaking of their tank's size refers to them as the size that they are....as if nothing were in it. Unless someone knows a formula for how much water LR/lb displaces I will continue to go with 205gal. There is also a density issue with the LR that complicates figuring that out. Your 95.2/170 works out to 56%...or, looking at it the other way, 44% of your system taken up by LR & LS, etc. I am quite certain that I have more water in my system than 56%.
Also, I need some sort of benchmark and I do not intend to dump all the Mg in at once and then test, but rather I will add and test in intervals. So, hence the 205gal as a benchmark...and yes I agree that I will probably have some left over, but it is not as expensive as some might believe, IMHO. Check out the price of a Kg at J&L. It is actually quite cheap, IMHO.

Cheers,