alkalinity and calcium usage by tank

aussiejohnny

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i seem to be maintaining my calcium levels at 420 with daily small dose but when testing my alkalinity for 3 days it dropped by .3 dkh a day and then for 2 days it maintained that level ...10.6 i was letting it drop naturally and now im wondering why it stopped depleting ..could the regular calcium dose buffer alk ? from what ive read alkalinity would be used up quicker than calcium ..on that thought if i maintain 420 calcium is there a matching ideal number to aim for in alkalinity not just a range ?
 

Mebbid

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It's possible that the level of alkalinity that you were dosing to maintain was precipitating out. Magnesium is what keeps the alkalinity from precipitating out, and if it's not high enough you won't be able to maintain higher levels of alkalinity.
 
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Justfebreezeit

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i seem to be maintaining my calcium levels at 420 with daily small dose but when testing my alkalinity for 3 days it dropped by .3 dkh a day and then for 2 days it maintained that level ...10.6 i was letting it drop naturally and now im wondering why it stopped depleting ..could the regular calcium dose buffer alk ? from what ive read alkalinity would be used up quicker than calcium ..on that thought if i maintain 420 calcium is there a matching ideal number to aim for in alkalinity not just a range ?

Also that's not a very fast consumption in general. You can test daily but since that consumption is so low I would use the weekly average to find a dose.

Our hobby test kits aren't accurate enough for trying to pin a number down to the tenth.
 
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aussiejohnny

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It's possible that the level of alkalinity that you were dosing to maintain was precipitating out. Magnesium is what keeps the alkalinity from precipitating out, and if it's not high enough you won't be able to maintain higher levels of alkalinity.
my calcium dose includes trace elements and magnesium ..i dont have a test for magnesium only gets checked at the lfs ..but according to directions proper mag is added with calcium ..using reef fusion 1.2
 
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Randy Holmes-Farley

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I don’t think there is anything unusual except that you are trying to accurately see small changes that are not reliably tested by kits.

I’d drop back to testing once a week, with a daily alk dose of 0.1 or 0.2 dKH per day and 1-2 ppm calcium and see how that trends over a few weeks. :)
 
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Randy Holmes-Farley

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my calcium dose includes trace elements and magnesium ..i dont have a test for magnesium only gets checked at the lfs ..but according to directions proper mag is added with calcium ..using reef fusion 1.2

I don’t recommend magnesium testing to guide dosing. It is not accurate enough.

What are you dosing for alk and calcium?
 
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Randy Holmes-Farley

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reef fusion 1/2 ..tanks doing great ..knowledge from this forum is amazing ..your knowledge is amazing

Thanks.

FWIW, despite its claim, reef fusion is not properly designed for 1:1 dosing of the two parts (it adds a little bit too much calcium), but at the demand level you are seeing, stick to 1:1 for now, based on the alkalinity changes (not calcium changes, which are too slow to be useful).
 
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