Add how much?! (Magnesium & Alkalinity)

[Luckyduck]

So I'm trying to get my Magnesium levels from 1250 currently to 1350. I'm doing all the math correctly 13.5 gallons x 100ppm x 0.03875 = 51.09 ml. Isn't that a lot?? I used the BRS calculator and Marine Depot and came up with the same number. It just seems like a lot and I want to be sure I'm not over dosing. I'm using Brightwell Magnesion Liquid. How quickly should I add that amount? I know not all at once. 10-15 ml twice a day till I get there? What's a safe way to add that much? Alk is a little low @ 8 DHK but I only need to add 9.5ml to get to 9.5 DHK which is where I want to be. Calcium is actually a little high @ 500 so I'm not currently dosing. Is it safe to add all 9.5ml of Alkalinity all at once? Or should I get the Magnesium levels right before I try and tackle the Alkalinity? 13.5 gallon tank, just a reminder.

 

[Copingwithpods]

I sometimes forget to test for mag and find myself in a bind where I have to dose 150ml+,sometimes 200ml+,i do it in 75ml doses, 75mls when I wake up another 75 when I go to sleep and so on. You can also do 25mls a day until you are with in range, no rush.

 

[Luckyduck]

I sometimes forget to test for mag and find myself in a bind where I have to dose 150ml+,sometimes 200ml+,i do it in 75ml doses, 75mls when I wake up another 75 when I go to sleep and so on. You can also do 25mls a day until you are with in range, no rush.

Oh okay. Thanks. That shouldn't take me long then to get it up. Even with a 13.5 gallon total water system 25 mls is okay to add at once? Just makin sure you remembered my tank size.

 

[legrunt]

I have a 16 gallon and needed to raise my mag by about 70ppm today. After calculating, i needed 42ml. Same like you, i thought that was a lot... So i dumped 20ml of magnesion first, and retested. That got me about halfway, so that gave me some assurance that the calculations were correct. I then proceeded to dump in another 20ml. I'm back into my green zone for magnesium, and no adverse reactions from corals, inverts or fish. Kinda leads me to believe that the rock steady stability requirement of alkalinity doesn't apply so much here...

Disclaimer: I may be wrong though...

 

[legrunt]

Oh, and from what i understand, better get your magnesium levels right first before trying to tackle alk and cal, cos low mag levels can cause your alk and cal to see saw...

 

[Luckyduck]

I have a 16 gallon and needed to raise my mag by about 70ppm today. After calculating, i needed 42ml. Same like you, i thought that was a lot... So i dumped 20ml of magnesion first, and retested. That got me about halfway, so that gave me some assurance that the calculations were correct. I then proceeded to dump in another 20ml. I'm back into my green zone for magnesium, and no adverse reactions from corals, inverts or fish. Kinda leads me to believe that the rock steady stability requirement of alkalinity doesn't apply so much here...

Disclaimer: I may be wrong though...

Awesome thanks for sharing your experience. Sounds like we are/were in the same boat. I trust these calculations now especially after hearing what you just said. I'm going to dump 25 ml in this morning another 25 tonight and 25 more tomorrow morning. I'm actually at 1200 PPM I just tested it so I need to come up 150 points which equals 77 ml.

 

[Luckyduck]

Oh, and from what i understand, better get your magnesium levels right first before trying to tackle alk and cal, cos low mag levels can cause your alk and cal to see saw...

I believe that's also true my friend. I will nail down these magnesium levels before messing with my alkalinity and hopefully my calcium will balance back out on its own as well.

 

[dbowman5]

this is from their tech instructions.
If the initial [Mg2+] in the aquarium is below 1,288 ppm, add this product at the maximum rate of 10 ml per 20 US-gallons daily until the desired concentration is attained, then dose daily or weekly as needed (see below). Always try to maintain the [Mg2+] within a range of +/-10 ppm.

51 mls, for you, might be 6.75 ml/day. My Mg was 975 but the total salinity was low. when i calibrated the refract i found that out. raising the salt level brought the Mg and every thing else up. I think you can add the Magnesion faster but for stability, the 10 ppm increment is better.

 

[Luckyduck]

this is from their tech instructions.
If the initial [Mg2+] in the aquarium is below 1,288 ppm, add this product at the maximum rate of 10 ml per 20 US-gallons daily until the desired concentration is attained, then dose daily or weekly as needed (see below). Always try to maintain the [Mg2+] within a range of +/-10 ppm.

51 mls, for you, might be 6.75 ml/day. My Mg was 975 but the total salinity was low. when i calibrated the refract i found that out. raising the salt level brought the Mg and every thing else up. I think you can add the Magnesion faster but for stability, the 10 ppm increment is better.

I must have read their tech instructions 10 times lol I'll dose at 20 ml in the morning and again at night till I get there. My salt water is premixed without additives. Just purified PH balanced ocean water so it will not raise my levels. I want to make my own adjustments and add my own chemicals ; I have them. Salinity is perfect I keep it at a consistent 1.0255. I had been dosing Magnesion several times over the week @ 5ml and was wondering why my levels weren't going up, in fact they dropped 50ppm by the end of the week. Now I know; cuz i need to add 75 ml. What pulls magnesium out of the water? Do corals use it just like Ca and Alk?

 

[Randy Holmes-Farley Verified Community Expert]

I must have read their tech instructions 10 times lol I'll dose at 20 ml in the morning and again at night till I get there. My salt water is premixed without additives. Just purified PH balanced ocean water so it will not raise my levels. I want to make my own adjustments and add my own chemicals ; I have them. Salinity is perfect I keep it at a consistent 1.0255. I had been dosing Magnesion several times over the week @ 5ml and was wondering why my levels weren't going up, in fact they dropped 50ppm by the end of the week. Now I know; cuz i need to add 75 ml. What pulls magnesium out of the water? Do corals use it just like Ca and Alk?

So let's try to understand what exactly you are using. Perhaps the place you get this from is misleading you.

Natural seawater with a specific gravity of 1.0255 (you say its perfect,a nd it is fine, but it is below 35 ppt salinity) and that seawater will have lower than normal amounts of magnesium and calcium.

I'd also be very wary of what pH balanced actually means. It can mean different things to different people, and some things some folks may do will raise alkalinity.

Totally perfect average seawater with a sg of 1.0255 will have a magnesium level of about 1236 ppm. That is pretty much in line with what you measured.

It does take a lot of solid material to boost magnesium because most solid magnesium supplements are only about 11% magnesium by weight.

 

[Randy Holmes-Farley Verified Community Expert]

Your magnesium did not drop 50 ppm in a week for any reason other than test error, or falling salinity. Doesn't happen in a week. Maybe in a year.

 

[dbowman5]

So let's try to understand what exactly you are using. Perhaps the place you get this from is misleading you.

Natural seawater with a specific gravity of 1.0255 (you say its perfect,a nd it is fine, but it is below 35 ppt salinity) and that seawater will have lower than normal amounts of magnesium and calcium.

I'd also be very wary of what pH balanced actually means. It can mean different things to different people, and some things some folks may do will raise alkalinity.

Totally perfect average seawater with a sg of 1.0255 will have a magnesium level of about 1236 ppm. That is pretty much in line with what you measured.

It does take a lot of solid material to boost magnesium because most solid magnesium supplements are only about 11% magnesium by weight.

Randy, he is using 'Brightwell Magnesion liquid', are their numbers accurate as far as dosing suggestions?

 

[Luckyduck]

Correct, Brightwell Magnesion liquid. Must have been error in testing then that it dropped. I'm gonna go to the LFS today, and have them test the major 3 for me just to be certain of my test numbers. Don't laugh at me but I buy my water from Petco. It's their own brand. Imaginatrium. It's in expensive and seems to work well so far. I say PH balanced meaning whatever they mean by writing it on the box. And in turn I won't add anything if it doesn't need it. Maybe I should switch to a more well known brand like Nature's Ocean? If the Imagitarium is fine though I would like to stick with it because it's only $11.50 for a 5 gallon jug. Natures Ocean is $20 for a 4.4 gallon. I liked that the Imaginatrium wasn't fortified like Nature's Ocean is as I don't mind testing and adding. Is it better to look at the PPT side of the refractometer? I will start to shoot for 35 PPT.