Boomer, got you covered on this! Already printed it up for 30 gallon water changes over the next month or so.
Thanx.
Thanx.
Magnesium
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DonW said:
Don,
I do not believe it is really a "formula" per say. Notice that the balanced "line" is indeed a straight line. This means it is a simple ratio between Calcium and Alkalinity. The "balanced" part of it comes from the ratio found to be present in natural sea water. Notice how the line cuts dead center throught the value of natural sea water. That ratio, in terms of the molar ratio between Ca and total Alk, is just maintained through out the line. It is basically natures magic number. The ratio of Ca and Alk is not stoichiometric when related to Calcium Carbonate. That is to say that there is a LOT more Ca than Alk. Here is a link that explains things in more detail:
http://www.reefkeeping.com/issues/2002-04/rhf/feature/
DonW said:
No drawback. In fact you could just pour it directly into your sump if you wanted to in dry form. May not be the most elegant solution but it would work. Just be sure to do it over a few days or weeks so you don't raise salinity too far too fast. Some animals are more sensitive to changes in salinity than others.....C
I have Tested my Oceanic at 36ppt and it comes out to 500ppm Ca and 1500ppm Mg
I emailed Oceanic today and this is the Response that I got back from them
"At a specific gravity of 1.021 – 1.023 Oceanic sea salt yields calcium concentrations of 420 – 480 ppm which are comparable to natural sea water.
Some reef tank aquarists prefer to maintain their tanks at a specific gravity of 1.025 or greater. With Oceanic salt, this high specific gravity results in calcium levels that can exceed 550 ppm which can disturb the delicate carbonate/bicarbonate equilibrium causing transient pH fluctuations. For reef tanks it is recommended that Oceanic salt be used at 1.024 specific gravity which should yield high calcium and magnesium levels without causing hardness and pH imbalance.
We have talked with the scientist who formulated our salt about this issue. He does not feel the formulation should be changed. Here are some suggestions that were given from him for aquarist who feel it is necessary to run their tanks and higher specific gravity.
1) Mix Oceanic salt to sg 1.023. To this slowly add and completely dissolve solid analytical reagent grade sodium chloride to desired sg. This procedure will increase sg without effecting calcium and magnesium levels.
2) Mix Oceanic salt to sg 1.023 – 1.025. Before adding to tank, treat with dKh hardness buffer to attain dKh of 5-7. Add gradually to tank after solution has equilibrated. "
HTH<
James
I emailed Oceanic today and this is the Response that I got back from them
"At a specific gravity of 1.021 – 1.023 Oceanic sea salt yields calcium concentrations of 420 – 480 ppm which are comparable to natural sea water.
Some reef tank aquarists prefer to maintain their tanks at a specific gravity of 1.025 or greater. With Oceanic salt, this high specific gravity results in calcium levels that can exceed 550 ppm which can disturb the delicate carbonate/bicarbonate equilibrium causing transient pH fluctuations. For reef tanks it is recommended that Oceanic salt be used at 1.024 specific gravity which should yield high calcium and magnesium levels without causing hardness and pH imbalance.
We have talked with the scientist who formulated our salt about this issue. He does not feel the formulation should be changed. Here are some suggestions that were given from him for aquarist who feel it is necessary to run their tanks and higher specific gravity.
1) Mix Oceanic salt to sg 1.023. To this slowly add and completely dissolve solid analytical reagent grade sodium chloride to desired sg. This procedure will increase sg without effecting calcium and magnesium levels.
2) Mix Oceanic salt to sg 1.023 – 1.025. Before adding to tank, treat with dKh hardness buffer to attain dKh of 5-7. Add gradually to tank after solution has equilibrated. "
HTH<
James
Boomer
Well-known member
At a specific gravity of 1.021 – 1.023 Oceanic sea salt yields calcium concentrations of 420 – 480 ppm which are comparable to natural sea water
They are lost in the fog. SG has been a very complicated subject for many even though it is easy. NSW at the these SG levels yes, if the temperature calibration point of the hydrometer is 60 F. And I am assuming that they are using a lab grade SG meter, calibrated to 60 F. Thus, these given Sg @ 1.023 = 34.4 ppt if the tank temp is 82 F. Most of the floating hydrometers, we use, are calibrated to 75 F or 77 F, which gives a 1.023 @ 77 F of 30.7 ppt. I do not know of a coral reef that has a salinity that low. And or are they confused, like many, that SG they gave is not SG but Density. SG and Density are NOT the same thing. In seawater chemistry SG is not used, density is, and often unknowing authors just change the word Density to SG....that is incorrect. As temp rises SG and density move apart. At max density of seawater they are equal but has the temp rises, say to 82 F there is a "4 point" difference.
When ever ANYONE gives an SG value it needs to state some things;
Is it a
1. Hydrometer, what kind, floater, swing arm, etc. and calibrated to what temp.
2. Refract, is it corrected for by the "15 unit " error.
3. Temp of water being tested.
4. Do these "meters" have ATC
With out these these values they gave or any one gives are meaningless IMHO
It is not up for debate, their salt is to high in Ca and Mg
They are lost in the fog. SG has been a very complicated subject for many even though it is easy. NSW at the these SG levels yes, if the temperature calibration point of the hydrometer is 60 F. And I am assuming that they are using a lab grade SG meter, calibrated to 60 F. Thus, these given Sg @ 1.023 = 34.4 ppt if the tank temp is 82 F. Most of the floating hydrometers, we use, are calibrated to 75 F or 77 F, which gives a 1.023 @ 77 F of 30.7 ppt. I do not know of a coral reef that has a salinity that low. And or are they confused, like many, that SG they gave is not SG but Density. SG and Density are NOT the same thing. In seawater chemistry SG is not used, density is, and often unknowing authors just change the word Density to SG....that is incorrect. As temp rises SG and density move apart. At max density of seawater they are equal but has the temp rises, say to 82 F there is a "4 point" difference.
When ever ANYONE gives an SG value it needs to state some things;
Is it a
1. Hydrometer, what kind, floater, swing arm, etc. and calibrated to what temp.
2. Refract, is it corrected for by the "15 unit " error.
3. Temp of water being tested.
4. Do these "meters" have ATC
With out these these values they gave or any one gives are meaningless IMHO
It is not up for debate, their salt is to high in Ca and Mg
DonW
R.I.P.
I'm a bit slow. If I calibrate my atc refractomter with the solution temp at 60 degrees. I then mix water to 35ppt@80 degrees according to refractometer. What is it in sg and ppt in reality.
Thanks
Don
Thanks
Don
Boomer
Well-known member
First, what are you calibrating it to ? Calibrating it to fresh water really isn't calibrating it. Calibrating on any thing should be some where near the value you are trying to reach. If you set it to freshwater at 0 ppt then you are about at 33.5 ppt the "15 unit" rule ( your 35 ppt - 1.5 = 33.5). You want to get near 35 ppt, so the reading should be 35 (NSW) + 1.5 = 36.5 ( what the refract should read to = NSW at 35 ppt. The ATC corrects for temp automatically, so tank temp is OK, not need to go down to 60 F. You will usually get the best or more assured results at 77 F, even with ATC.
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No kiddin thats the second reply I have seen from them with that kind of reasoning. Its a shame the salt mixes very well and seem ok in the other catagories, but with the mag and cal at those levels its pretty much unusable.
Mike
Boomer
Well-known member
I guess Mike, Randy, who tested some, doesn't know what he is doing :lol:
and seem ok in the other catagories
There have been a number of low alk Mojo
and seem ok in the other catagories
There have been a number of low alk Mojo
My alk doesnt seem that Low.. It mixes up at
500 Ca
1500 Mg
6-7dkh
7.9 - 8.0 pH
the good thing is the buckets seem really consistent with each other.. When Mixing at a lower salinity like they say it seems to be the perfect salt.. Someone Mentioned Water Softning salt is the Same solt that can be Used for tanks? Is this true? Can I mix my salt at like 1.022 and raise with the Water softner salt to 1.026 like Oceanic says? Is there any danger in doing this? I was close to picking up some IO today to balance the 2 out..
James
500 Ca
1500 Mg
6-7dkh
7.9 - 8.0 pH
the good thing is the buckets seem really consistent with each other.. When Mixing at a lower salinity like they say it seems to be the perfect salt.. Someone Mentioned Water Softning salt is the Same solt that can be Used for tanks? Is this true? Can I mix my salt at like 1.022 and raise with the Water softner salt to 1.026 like Oceanic says? Is there any danger in doing this? I was close to picking up some IO today to balance the 2 out..
James
Stircrazy
Well-known member
Boomer said:
Boomer, is there a known deviation for different makes of swing arm testers?
I use the Coralife deepsix myself but if there was a known deviation in this brand it would be good to know.
Steve
From what I have found with the Deep six is it was about .003 off from all my testing of them... Only tried 3 different ones from my Refract but they were all .003 off roughly... If your at .027 then you are really at .030 I would suggest .024 being safe for the DeepSix..
James
James your parameters are way off for alk. For NSW at 35ppt your calcium should be 415, mag=1290 and alk around 7.5dkh. If you are mixing the salt at 35ppt and getting 500 for cal and 1500 for mag its telling you that you that your calcium is over 20% to much and your mag is about 15% to high, while at the same time your alk is around 10% low. Just wacky.
Here is the way to look at it. if your SW is at 1.027 the calcium level should be 415 and mag 1290. If you drop your salinity to 1.026 you have reduced it 3.5% so all levels of elements would drop by that same 3.5%, so cal=400 and mag=1244.
So if thier saying you should mix the salt up at 1.023 then if ll the elements in the SW went in balanced the cal should be 356 and your mag would equal 1109. Make sence??
So what they are really saying is that they put to much mag and cal in the formula and they want you to mix it at a lower salinity and then buffer it up with a salt that does not have cal or mag in it, Or take thier mix with the high cal and mag and try to beat them down by buffering the heck out of it.
The right answer would be oooppps we will start making it proper so you can just mix it and put it in your tank.
Mike
Here is the way to look at it. if your SW is at 1.027 the calcium level should be 415 and mag 1290. If you drop your salinity to 1.026 you have reduced it 3.5% so all levels of elements would drop by that same 3.5%, so cal=400 and mag=1244.
So if thier saying you should mix the salt up at 1.023 then if ll the elements in the SW went in balanced the cal should be 356 and your mag would equal 1109. Make sence??
So what they are really saying is that they put to much mag and cal in the formula and they want you to mix it at a lower salinity and then buffer it up with a salt that does not have cal or mag in it, Or take thier mix with the high cal and mag and try to beat them down by buffering the heck out of it.
The right answer would be oooppps we will start making it proper so you can just mix it and put it in your tank.
Mike
Boomer
Well-known member
Mike
Well that would be a direct result of the mag and cal levels no??
No, you just add more MgCl and CaCl with little baking soda added
Well that would be a direct result of the mag and cal levels no??
No, you just add more MgCl and CaCl with little baking soda added
Boomer
Well-known member
Jim
I don't' like the Deep Six. Every one I've seen is way off and may others have tested them and finding them way off. .003 is way off
It should be no more off than .001 and max at .002.
Boomer, is there a known deviation for different makes of swing arm testers?
No, generally. It depends, if there are made of thermal expansion plastic, which is like automatic temp compensation. The only swing arm I trust is the SeaTest, which I now does this and is CARED for properly. On the avg, the SeaTest's we have played with, are 1 ppt to low. Mine is right on the nuts
I don't' like the Deep Six. Every one I've seen is way off and may others have tested them and finding them way off. .003 is way off
It should be no more off than .001 and max at .002.Boomer, is there a known deviation for different makes of swing arm testers?
No, generally. It depends, if there are made of thermal expansion plastic, which is like automatic temp compensation. The only swing arm I trust is the SeaTest, which I now does this and is CARED for properly. On the avg, the SeaTest's we have played with, are 1 ppt to low. Mine is right on the nuts
Hey Mike I hear ya there.. That is by far not the Answer that I wanted from them but What more can I do... I have my own Ideas but I would like to stay here with my Family LOL... The Ca I am not too worried about I got it down pretty low in the tank.. about Ca 450 and Alk 8.3ish Dkh... My Mg is still 1500... Thats what my goal is I want the Mg lower... I am fairly confident that if it was atleast 1400 that my pH issues in my tank would be corrected as well. not really an issue 7.9-8.2 but I dont like that... I am looking for an Easy way to even just drop the Mg in the WC bucket so that when i do my water changes it will lower it slowly... any suggestions without changing salt or lowering the Sg lower than 35ppt... I mean Everything in my tank loves the salt and I am getting mass growth and no algae.. Just that high Mg bothers me..
James
James
James I dont really know a way to lower the mag in the bucket, maybe the addition of alk buffer will percipatate it out, but that more of a Collin, or Boomer question.
Watch the calcium level though, remember calcium is a waste product for corals and it inhibits the coral tissue growth. To rid itself of the calcium the coral has to use energy, the higher the level the harder your making the coral work, and the more energy it has to divert from other needed activities.
MIke
Watch the calcium level though, remember calcium is a waste product for corals and it inhibits the coral tissue growth. To rid itself of the calcium the coral has to use energy, the higher the level the harder your making the coral work, and the more energy it has to divert from other needed activities.
MIke
I'm not clear why you are worried about slightly high Mg levels. I do not think the Mg is the cause of your pH problem. Even if they were, the difference between 1300 and 1500 would not cause such a significant deviation in pH. I certainly would not suggest trying to precipitate out your Mg. It would likely co-precipitate with something else and runs the risk of causing more problems than it is worth. Withough changing salts or doing only very infrequent water changes and just letting the Mg drop naturally, I'm not sure there is a good way to lower it after the fact. I don't think it is even worth worrying about though. If you are happy with your salt. Just stick with it and balance it as best you can. Adding pure NaCl to change the ratio of bulk salt to Mg levels is about the only way that is reasonable. If it is a problem...consider changing salts. This is a know deficiency of the brand you are using.
Sincerely...Collin
Sincerely...Collin
mojoreef said:
