I have a Reefer 250 and began dosing about 1 month ago. I am using Oceans Blend 2 part. However, I find myself having to rarely dose Ca. Today I bought the Neptune DOS to automate this portion of my day. From what I have read I should be dosing close to equal amounts of Alk and Ca but I cannot figure out why I need more Alk than Ca. I dose 16 ml a day of Alk and only need to dose Ca about every 3-5 days. Today i tested my Mag and it was at 1250. The tank is stocked with a pistol shrimp, goby, two clowns, exquisite wrasse, spotty blenny, Acropora, hammer head, torch, zoa, Favia, and a trachy. There are also numerous snails and crabs. Is there any particular reason why there is not a demand for Ca.
Help dosing
- Thread starter glavaron
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What's your WC schedule? It's not uncommon to have to dose just the alk portion, since the WC's will keep up with Ca and Mg...depending on your load. The normal uptake of Alk and Ca is a ratio of 5:2 ~ 50ppm(2.8dKH) of alk to every 20ppm of Ca.
There's a procedure I think it prudent to follow to help to minimize the effects of WC's on dosing.
First, if you're not using the entire package, would be to thoroughly mix the salt mix to make sure there was no elemental stratification that may have occurred during shipping, and you're getting the proper proportions of all the elements, i.e. Ca, Mg, Alk, etc., with each measure of salt mix when you make up your WC water.
Secondly, following proper mixing procedures, i.e. using RO/DI water, adding the salt mix to the water, etc., I would make sure to accurately get the SG you want, I preferred 1.026(35ppt), using a properly calibrated measuring device, i.e. refractometer calibrated with a 35ppt solution(not plain water), to ensure the same amount of these elements with each WC. Using a swing arm type of hydrometer, or other non/mis calibrated device can cause differences in your SG when you make up your WC water, and further skew a dosing schedule. Using a decent set of test kits, i.e. Salifert, Red Sea Pro, etc., measure your Mg first, making sure it’s between 1200-1400ppm, then your Alk and Ca.
Next, I would set and keep a schedule of WC's in terms of both frequency, i.e. weekly, bi monthly, monthly, etc. and volume, i.e. 10%, 15%/10 gal.,15 gal., etc. to help minimize any skewing that may normally occur, since this is where you're adding/replenishing those elements in an ongoing basis.
Depending on a particular load in any system, it's likely that you may need to adjust your dosing based on a particular WC schedule, i.e. the disproportionate use of Alk vs Ca supplement, since the WC is better at keeping up with the Ca needs. You may notice that, with regular WC's, you may never have to dose any Mg, since there is very little of it used (about 1/10th of your Ca use), and its replenished with regular WC's.
First, if you're not using the entire package, would be to thoroughly mix the salt mix to make sure there was no elemental stratification that may have occurred during shipping, and you're getting the proper proportions of all the elements, i.e. Ca, Mg, Alk, etc., with each measure of salt mix when you make up your WC water.
Secondly, following proper mixing procedures, i.e. using RO/DI water, adding the salt mix to the water, etc., I would make sure to accurately get the SG you want, I preferred 1.026(35ppt), using a properly calibrated measuring device, i.e. refractometer calibrated with a 35ppt solution(not plain water), to ensure the same amount of these elements with each WC. Using a swing arm type of hydrometer, or other non/mis calibrated device can cause differences in your SG when you make up your WC water, and further skew a dosing schedule. Using a decent set of test kits, i.e. Salifert, Red Sea Pro, etc., measure your Mg first, making sure it’s between 1200-1400ppm, then your Alk and Ca.
Next, I would set and keep a schedule of WC's in terms of both frequency, i.e. weekly, bi monthly, monthly, etc. and volume, i.e. 10%, 15%/10 gal.,15 gal., etc. to help minimize any skewing that may normally occur, since this is where you're adding/replenishing those elements in an ongoing basis.
Depending on a particular load in any system, it's likely that you may need to adjust your dosing based on a particular WC schedule, i.e. the disproportionate use of Alk vs Ca supplement, since the WC is better at keeping up with the Ca needs. You may notice that, with regular WC's, you may never have to dose any Mg, since there is very little of it used (about 1/10th of your Ca use), and its replenished with regular WC's.
Randy Holmes-Farley
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You ikely need more alk than calcium simply because your salt mix likely has more calcium than the balanced amount of alk.
But I'll bet that if you just dosed equal parts always, in an amount to maintain alkalinity, calcium will not get too high (or will take a very long time to get too high). It moves up and down far more slowly when over or under dosing than does alkalinity, and equal parts dosing will likely keep it at about the level in your salt mix.
But I'll bet that if you just dosed equal parts always, in an amount to maintain alkalinity, calcium will not get too high (or will take a very long time to get too high). It moves up and down far more slowly when over or under dosing than does alkalinity, and equal parts dosing will likely keep it at about the level in your salt mix.
Randy Holmes-Farley
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Randy Holmes-Farley
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Higher magnesium reduces the likelihood of abiotic precipitation of calcium carbonate on pumps and such, so may reduce the demand for alkalinity and calcium for that reason.
