Low magnesium
Printed From: Utah Reefs
Category: Specialized Discussion
Forum Name: Reef Chemistry
Forum Description: A place to discuss reef chemistry.
URL: http://www.utahreefs.com/forum/forum_posts.asp?TID=45866
Printed Date: December 12 2025 at 12:30pm
Software Version: Web Wiz Forums 12.03 - http://www.webwizforums.com
Topic: Low magnesium
Posted By: Davidwillis
Subject: Low magnesium
Date Posted: January 07 2011 at 1:09pm
|
I just got my magnesium test kit, and I think this may be some of my problems. Here are all my parameters: Mag- 850 alk 9 calcium 440 ph 8.1 ammonia 0 nitrite 0 nitrate 0 phosphate 0.25 temp 76 I also got some c-balance I was going to start using, but I think I need things balanced before I can start that... Should I add some Epsom salt? Thanks
|
Replies:
Posted By: tileman
Date Posted: January 07 2011 at 1:15pm
|
That is low. You want it up around 1300 II can't advise you on epsom salt as I've never used it. I have always used Kents Tech M ------------- 335G Reef TOTM. http://www.advancedaquarist.com/2015/2/aquarium ReefKeepers TOTM Feb. 2012 http://reefkeeping.com/joomla/index....k-of-the-month & |
Posted By: Davidwillis
Date Posted: January 07 2011 at 1:19pm
| Yes, maybe I should just do some water changes. If I add that much epsom salt I will also add a lot of sulfate. I looked at petsmart (the local fish store), and they don't have anything to add magnesium. |
Posted By: tileman
Date Posted: January 07 2011 at 1:23pm
|
A water change will help, Check again after W/C and see how much it goes up. ------------- 335G Reef TOTM. http://www.advancedaquarist.com/2015/2/aquarium ReefKeepers TOTM Feb. 2012 http://reefkeeping.com/joomla/index....k-of-the-month & |
Posted By: Mark Peterson
Date Posted: January 07 2011 at 2:48pm
|
Don't worry. It would take a year of adding Epsom Salt with no water changes to cause any problems. You have adequate biofiltration which includes the sulfur cycle to handle the Epsom Salt. Water changes won't get you close to the amount of Mg needed, unless you plan to do a 90% change. Don't let common new hobbyist paranoia get the best of you.  ------------- Reefkeeping Tips, & quick, easy setup tricks: www.utahreefs.com/forum/forum_posts.asp?TID=9244 Pay it forward - become a paid WMAS member 
|
Posted By: Davidwillis
Date Posted: January 07 2011 at 2:54pm
| Thanks Mark. I will go ahead and raise it with epsom salt, then hopefully the c-balance will keep it in the correct ratio from then on. |
Posted By: Lewy
Date Posted: January 07 2011 at 4:14pm
|
I use a combination of epsom salt and a magnesium cloride ice melt disolved in RO to raise my levels. ------------- 40 gal w/ 20 sump |
Posted By: Davidwillis
Date Posted: January 07 2011 at 4:55pm
|
How do you know which ice melt is pure magnesium chloride? I have to go get some epsom salt anyway, so if I can find an ice melt that is magnesium chloride I will get that too. Also, do I have to be careful and not raise my magnesium too fast?
|
Posted By: Lewy
Date Posted: January 07 2011 at 6:51pm
|
Slow is best. Mark would know how fast you can increase it daily. I use 'safe step' brand. it's called, I believe, 'extreem 8500' ------------- 40 gal w/ 20 sump |
Posted By: badfinger
Date Posted: January 07 2011 at 7:00pm
| What kind of salt are you using in your water changes?..... I would use both mag chloride, and epsom salt. Both are required to make it balanced... you could probably find like a chemical company that sells or could order you in mag chloride (if you can't find it in a ice melt).. or just order it from bulk reef supply still pretty cheap |
Posted By: Davidwillis
Date Posted: January 08 2011 at 10:01am
|
I use instant ocean salt, although I do very few water changes. My goal is to figure out how to maintain water quality without water changes (or at least very few). Is there a formula to figure out how much epsom salt to add? I added a table spoon disolved in ro water to my sump last night, but this morning I did not see any increase in magnesium. So I figure I probably should calculate how much I will need to add. I guess Ideally I would add 9 parts magnesium chloride to 1 part epsom salt. But I don't have magnesium chloride, so I will just use epsom salt for now.
|
Posted By: Davidwillis
Date Posted: January 08 2011 at 10:04am
|
found a calculator... http://reef.diesyst.com/chemcalc/chemcalc.html - http://reef.diesyst.com/chemcalc/chemcalc.html
Looks like it will take about 3 3/4 cups to raise it to 1300
|
Posted By: badfinger
Date Posted: January 08 2011 at 11:02am
|
Do not add in all 3 3/4 cups all at once that needs to be done over a week or two...also instant ocean is not high in cal,alk,mag,strontium so waterchanges with instant ocean will not help your levels too much.... for an alk/cal supplement I use kalkwasser(aka pickling lime,aka calcium hydroxide) and I love it... I just use kalk in with all my top off water.
Cal/alk/mag are your 3 major elements in your water that you need to make sure are pretty stable(stable being more important then precise numbers)... so to me I would not just add in epsom salt or known as magnesium sulfate... sulfate is sulfur.. chloride is always the better "transporter" of anything cal/mag/strontium etc etc etc... so to get a "perfect balance" you need to use both mag chloride(in a lot higher of quantity then mag sulfate) and mag sulfate. |
Posted By: badfinger
Date Posted: January 08 2011 at 11:11am
|
And I also wanted to add that when salt (reef crystals, aquavitro salinity, h20) or any reef salt... if made to like a level of 1.026 basically puts all your levels cal/alk/mag/strontium at correct levels for that batch. And so if you are only doing a 20% water change.. you are only replacing 20% of trace elements.(in this case hopefully your tank is only using up 20% of trace elements inbetween every water change)
Brad syphus quoted sombody once saying.... to keep your levels correct you would have to do a 100% water change every day |
Posted By: Davidwillis
Date Posted: January 08 2011 at 11:13am
|
The calculator says not to increase the magnesium by more than 100 ppm per day, which comes to about 3/4 cup per day of epsom salt. If I could find some magnesium chloride locally I would use it. I will look again next time I am at lowes, home depot, or walmart. Once I get my mag, calcium, and alk where I want it I can use my c-balance (which has calcium, magnesium, strontium, etc).
|
Posted By: tileman
Date Posted: January 08 2011 at 11:34am
|
http://reefkeeping.com/issues/2006-02/rhf/index.php - An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com This is a good read. ------------- 335G Reef TOTM. http://www.advancedaquarist.com/2015/2/aquarium ReefKeepers TOTM Feb. 2012 http://reefkeeping.com/joomla/index....k-of-the-month & |
Posted By: Davidwillis
Date Posted: January 08 2011 at 12:38pm
|
I did some more testing today, and I am not sure I am using my test kit correctly. I am using the red sea magnesium kit. After adding the A, and the B, you add the C until it changes from pink to blue (there is a color chart). When I get to about 850 it changes from pink to a blue/purple (but not as blue as the chart). After adding a few more drops it stays that color, so I thought that must be it. But today I tried adding more, and it went back to pink, then back to blue/purple (bluer than the first time, but it never gets all the way to the blue on the chart). The second change happens at about 1300, It may get slightly darker after adding more, but it never gets to the blue on the chart. So I guess I really have no idea what my magnesium is, so I am not going to add anymore until I figure this out. I have gone through the test 3 times following the instructions exactly, with the same results.
|