Ca ?

[chris&barb]

i came across this post elsewhere and was wondering what every one's thoughts were.

"High Ca levels are another hobby myth. Ca is not limiting to corals or any marine animals that use it.
Limiting means, it's not the factor that limits their ability to put down Ca skeletons.

Carbon = buffer = alk, is the limiting factor. And even that is not limiting unless it's way lower than what's recommended in the hobby. It is the buffer through. So high alk will 'buffer' your tank against pH swings.

Ca has not been shown to be limiting even at 50ppm.

Keeping high Ca levels will certainly cause you problems. Not just in the off chance that you crash you alk, but it will precipitate on your pumps, heaters, plumbing, UV if you are using one, etc etc."

 

[LakeEd]

Chris,

Those are very interesting comments and I, for one, look forward to Boomer's input! I had always understood (my limited understanding of our little parts of the ocean) that a calcium level lower than say about 350, would limit how well my SPS's could grow... which is why we strive to keep our tank's parameters at NSW levels.

 

[swissgaurd]

this is a good tag

vic

 

[chris&barb]

Ed, what really interested me about this is a few comments made later in the thread about how a lower Ca level will cause less precipitation on pumps ect.. but wont effect coral growth. i have always shot for NSW also but get a lot of precipitation, especially in GFO(making it useless in about 3 weeks) if this is true then i wouldn't have to clean my pumps every 2 weeks and could save a lot on GFO

 

[DonW]

Ed, what really interested me about this is a few comments made later in the thread about how a lower Ca level will cause less precipitation on pumps ect.. but wont effect coral growth. i have always shot for NSW also but get a lot of precipitation, especially in GFO(making it useless in about 3 weeks) if this is true then i wouldn't have to clean my pumps every 2 weeks and could save a lot on GFO

My question is why you have such bad precip? At NSW there should be very little percip. Does your tank consume large amounts of ca?

Don

 

[chris&barb]

My question is why you have such bad precip? At NSW there should be very little percip. Does your tank consume large amounts of ca?

Don

my tank is about 425g to 450g TWV. i use about 1200 to 1500ml (each) of Randys 2 part per day.

Ca 425ppm
Mg 1300ppm
Alk 8.5 dkh

i use dosing pumps, and levels are stable

 

[DonW]

my tank is about 425g to 450g TWV. i use about 1200 to 1500ml (each) of Randys 2 part per day.

Ca 425ppm
Mg 1300ppm
Alk 8.5 dkh

i use dosing pumps, and levels are stable

Dosing kalk? Any submersible pumps?

Don

 

[DonW]

my tank is about 425g to 450g TWV. i use about 1200 to 1500ml (each) of Randys 2 part per day.

Ca 425ppm
Mg 1300ppm
Alk 8.5 dkh

i use dosing pumps, and levels are stable

Just reread that. Thats over 30 tsp ca chloride per day and way over 25ppm consumption. Is this correct?

Don

 

[LakeEd]

Thats interesting to me as well. My levels are;
Ca 400-420ppm
Mg 1250-1300ppm
Alk 8.3-8.5

The variance depends on how well I'm keeping up with things, of course. I don't get very much (if hardly any) precip on my pumps at all. All of my pumps are external however, not sure if that is part of the reason???

 

[MikeS]

Calcium levels much above NSW values (420ppm) don't do much for corals, they can actually be harmful to a degree...because as the coral trys to rid it's tissue of the excess Ca, it does so at the expense of tissue growth, it's an energy budget thing...shoot for NSW values...

MikeS

 

[chris&barb]

thanks for everyone's input!

although my current situation may be pertinent to my original post, i really want to discuss the quote i quoted.

what i want to know is.

is this quote correct?

how high is too high? (before precipitation)

how low is too low? (before inhibited growth or any other detrimental effect)

i know Ph and Alk will come into everything, but for arguments sake let's say they are 8.2Ph and 7.5Alk

 

[pfish]

tagging along

 

[MikeS]

thanks for everyone's input!

although my current situation may be pertinent to my original post, i really want to discuss the quote i quoted.

what i want to know is.

is this quote correct?

how high is too high? (before precipitation)

how low is too low? (before inhibited growth or any other detrimental effect)

i know Ph and Alk will come into everything, but for arguments sake let's say they are 8.2Ph and 7.5Alk

How high is to high? hard to say...but like I said, it's an energy budget issue...if the coral in question is working too hard to rid is tissue of Ca, it does so at the expense of energy that could be used for tissue growth...

Too low?...not sure there is such a thing, all that will do is inhibit skeletal growth of the coral, it won't interfere with the normal metabolisim of the coral tissue itself...they don't "need" Ca to carry out the natural metebolic things they do to keep alive...

so back to my point, these animals have evolved over the years in the sea to do what they do...and thats why I think that maintaining NSW values is the way to go...don't exceede them...

MikeS

 

[Curtswearing]

This info might be too generic to be useful.

I don't know how low is too low. I cannot verify the 50 ppm because I've never run my tanks under laboratory experiments. (Nor would I BTW unless I was a scientist). Unfortunately, I don't have time to search for sources right now.

Regardless, the thing to remember is that Calcium is unwanted by stonies and they purposely create a micro-environment to get rid of it. They literally store it up and concentrate enough of Calcium to create a precipitation event. That's where the skeleton comes from. What happens when you overdose Calcium in your tank? A carbonate snowstorm. Exact same thing with stonies but on a smaller scale. But we do it on accident and the corals do it on purpose. Carbon in the form of carbonates and bi-carbonates are definately more important than Calcium levels.

To make things more complicated, there are a couple of stand-in elements that help in calcification.

With all of the above said, I agree with Mike.....match NSW levels to the best of your abilities and don't worry about the fact that Calcium isn't as limiting as much as most people believe. Because Ca levels impact Alk levels (which in turn impact pH levels), don't try to push one or the other. NSW is balanced and I would recommend striving for that.

 

[MikeS]

Regardless, the thing to remember is that Calcium is unwanted by stonies and they purposely create a micro-environment to get rid of it. They literally store it up and concentrate enough of Calcium to create a precipitation event. That's where the skeleton comes from.

Exactly...and in higher Ca environments, the energy they waste ridding the tissue of Ca they do at the expense of tissue gowth...keep it at NSW values...

MikeS

 

[Curtswearing]

in higher Ca environments, the energy they waste ridding the tissue of Ca they do at the expense of tissue gowth...keep it at NSW values...

Yup...that's the long and short of it.

 

[Boomer]

Chris

"High Ca levels are another hobby myth. Ca is not limiting to corals or any marine animals that use it.
Limiting means, it's not the factor that limits their ability to put down Ca skeletons."

Really, so if the Ca++ is zero where do they get it from ?? It is limiting to a degree. Corals need no more Ca++ than 360 ppm to grow. At what limit it becomes limiting I'm not sure but for the most part it is not limiting at all in any reef tank.

"Ca has not been shown to be limiting even at 50ppm."

Where or what study says this ? I hr and I can find no study that deals with Ca++ limitng in corals. There is one big reaon for this. Ca++ is not limited in the ocean.


"Carbon = buffer = alk, is the limiting factor. And even that is not limiting unless it's way lower than what's recommended in the hobby. It is the buffer through. So high alk will 'buffer' your tank against pH swings."


Carbon does not = buffer or Alk. It is buffer or Alk have carbon, so carbonate Alk/ buffer is a carbon soruce. Phosphates are buffers too and so is OH- and they have no carbon. CO2 is a Carbon soruce also and is not a buffer. So, that is a bad analogy but I know what is meant by it.

"Keeping high Ca levels will certainly cause you problems. Not just in the off chance that you crash you alk, but it will precipitate on your pumps, heaters, plumbing, UV if you are using one, etc etc."

I agree but in order to do the you have to have buffers to leave deposites or a high Alk. The Ca++ does not leave deposites as Ca++. They will either be carbonate or phosphate based. There is NO need to keep high Ca++ levels. IMHO they should not exceed 425 ppm, as there is no sound reason to be any higher. It is just best to keep them at NSW levels and the same for all ions if you can test for them.

 

[chris&barb]

Just reread that. Thats over 30 tsp ca chloride per day and way over 25ppm consumption. Is this correct?

Don

yes. i run dosing pumps 24/7. i have since lowered my Ca target to 385ppm and the precipitation has slowed significantly. my consumption rate has only reduced a minimal amount (probably 25 to 50ml per day)


why would lowering it (Ca) this amount stop precipitation? i dont think i was trying to keep it too high before.

test kits are new salifert

 

[DonW]

yes. i run dosing pumps 24/7. i have since lowered my Ca target to 385ppm and the precipitation has slowed significantly. my consumption rate has only reduced a minimal amount (probably 25 to 50ml per day)


why would lowering it (Ca) this amount stop precipitation? i dont think i was trying to keep it too high before.

test kits are new salifert

I wouldnt lower it. I run mine even higher. I was wondering based on your comment.
"i have always shot for NSW also but get a lot of precipitation, especially in GFO(making it useless in about 3 weeks) if this is true then i wouldn't have to clean my pumps every 2 weeks and could save a lot on GFO"

Stands to reason with this sort of precip something is off somewhere. 3 weeks and gfo is useless and cleaning pumps every two weeks is alot of precip.

Don

 

[moortim]

I have been working on learning more about calcium, magnesium and all that, so I am tagging along here.
Does anyone have any recommendations for a good book on this subject?

Tim