Calc Vs Alk

Bert0089

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What's more important Alk or calcium... I cannot seem to get my calc above 400 and I'm keen to start dosing all for reef but need my levels to be consistent before I can start The other parameters are attached. I'm fairly new to all this and as good as YouTube is it can become a bit of a minefield.
Thanks 🙏

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Dom

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What's more important Alk or calcium... I cannot seem to get my calc above 400 and I'm keen to start dosing all for reef but need my levels to be consistent before I can start The other parameters are attached. I'm fairly new to all this and as good as YouTube is it can become a bit of a minefield.
Thanks 🙏

What you need to understand is this: all chemistry numbers are important to a different degree. But it is the overall chemistry of the tank that is important.

Also understand that there are limits as to how high you can get calcium based on what your alkalinity number is.

As I understand it, alk and calcium are linked, because they both participate in the formation of calcium carbonate, which corals, clams, and coralline algae use to build skeletons and shells.

If you try to raise calcium too high without maintaining alkalinity in proportion, you can reach a point where Calcium Carbonate will precipitate out.

In the end, the maximum calcium level you can maintain in a reef tank is limited by your alkalinity. If alkalinity is too low, calcium can’t rise much without risking precipitation.




 
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Bert0089

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What you need to understand is this: all chemistry numbers are important to a different degree. But it is the overall chemistry of the tank that is important.

Also understand that there are limits as to how high you can get calcium based on what your alkalinity number is.

As I understand it, alk and calcium are linked, because they both participate in the formation of calcium carbonate, which corals, clams, and coralline algae use to build skeletons and shells.

If you try to raise calcium too high without maintaining alkalinity in proportion, you can reach a point where Calcium Carbonate will precipitate out.

In the end, the maximum calcium level you can maintain in a reef tank is limited by your alkalinity. If alkalinity is too low, calcium can’t rise much without risking precipitation.




But with an alk level of 10 my calc should surely be higher? As my LFS coral tanks are 8-9 and have calc levels of 450 or am I misunderstanding this? I really appreciate everyones help with this
 
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Dom

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But with an alk level of 10 my calc should surely be higher? As my LFS coral tanks are 8-9 and have calc levels of 450 or am I misunderstanding this? I really appreciate everyones help with this


Based on what I've read, struggles to get calcium elevated are connected to other chemistry, such as Mag, pH,and temperature, in addition to ALK.

Perhaps I missed it, but what problem are you trying to correct?

If nothing is wrong and you are chasing numbers, don't. Just be faithful to your water changes for a few months and see how everything shakes out. I think you will be happy.
 
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Randy Holmes-Farley

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If calcium is low, boost it with calcium chloride, and nothing can stop it from rising to your target if you add enough.

Raise alk slowly by ramping up the AFR over time until you get to your target level. There is no reason to get anything else for that purpose.
 
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Dom

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If calcium is low, boost it with calcium chloride, and nothing can stop it from rising to your target if you add enough.

Raise alk slowly by ramping up the AFR over time until you get to your target level. There is no reason to get anything else for that purpose.

Thank you for responding, Randy. I was hoping you would.
 
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Bert0089

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If calcium is low, boost it with calcium chloride, and nothing can stop it from rising to your target if you add enough.

Raise alk slowly by ramping up the AFR over time until you get to your target level. There is no reason to get anything else for that purpose.
Thanks I tested with my new salifert test kit and the reagent starts blue then when mixed goes pink, however doesn't turn back blue, is it possible I've got a dodgy kit?.... For information its the new 2 part kit not the older 3 part one. I tested with my old kit (NYOS, 3 part kit, past expiry date) and it read my calc at 465 so it has definitely come up... Cheers
 
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