Recommended alk cal, and mag for reef and fish
- Thread starter Toste
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Good question. My opinion/experience:
Alk: This is most important. I recommend 8.4 dkH, +/- 1.0 as the 'Green zone'. +/- 2.0 dkH as Yellow. And outside of that as Red/Danger zone. Its a little more complicated than this, but its a solid starting point to learn the ropes.
Calc: moderate importance. Aim for at least 435ppm. You can go higher, but it doesnt necessarily help. I try to keep mine under 500 so as to not waste calc supplements, nor test kit reagent.
Mag: low-moderate importance. I recommend at least 1280ppm, but not too much higher unless you have a specific reason such as if youre battling certain few pests that dont like high magnesium. Id suggest keeping it under 1450ppm
Alk: This is most important. I recommend 8.4 dkH, +/- 1.0 as the 'Green zone'. +/- 2.0 dkH as Yellow. And outside of that as Red/Danger zone. Its a little more complicated than this, but its a solid starting point to learn the ropes.
Calc: moderate importance. Aim for at least 435ppm. You can go higher, but it doesnt necessarily help. I try to keep mine under 500 so as to not waste calc supplements, nor test kit reagent.
Mag: low-moderate importance. I recommend at least 1280ppm, but not too much higher unless you have a specific reason such as if youre battling certain few pests that dont like high magnesium. Id suggest keeping it under 1450ppm
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Once you figure out approximately where you want the above parameters (alk/calc/mag) to be for your specific tank that will help you determine which salt mix to use. Different mixes (even within the same brand) will have different values for alk/calc/mag at a given salinity value, printed on the bucket. We for instance a while back changed from using Red Sea Coral Pro (much higher alk, around 11-12dkH), to Red Sea Blue Bucket (alk around 8.3dKH). We were maintaining our target values for alkalinity closer to 8 in the tank with 2-part solution between water changes. When doing water changes it makes sense to use a salt mix that will be close to your tanks target parameters. This will help avoid a sudden parameter shift. Even when we matched salinity with the Coral Pro above to our tanks salinity, the alkalinity was much higher in the newly mixed salt water and that caused swings that scaled with how big of a water change we did. Also, if you're just starting out you are unlikely to need to start dosing anything related to the above big 3 (alk/calc/mag) because your tanks consumption of these is likely to be very low. Replenishment of these and other trace elements will be accomplished by weekly/bi-weekly water changes.
Thank you so much for the feedback. I am using the Red Sea Coral Reef Pro and my all is sitting at about 9.9 but has been slowly diminishing over the days. I do daily water changes of 2 gallons. My Calc is 617 and my mag is 1270. I am hoping that I will not need to dose but if I do I want to start early.
Another good rule of thumb is don't dose anything you are not willing to also test for. Adding supplements blindly to a system is a good way to throw things out of whack.
I charted the above data, and a couple others. And added my above recommendation at the end. Much of the time, i find making visuals for people helps to communicate.
Pardon the spacing, this was a rough draft and i should have given Alk more room on the paper. Ill program a better visual in the future. This is a popular question, and this is roughly the approach i take to everything... look at a large batch of the collective data, bigger than this, and make my own assessment. Then through experience, modify my assessment over time.
Veterans, would you like for me to plot all your recommendations as well? It would be cool to get the collective ARC recommendations.
Pardon the spacing, this was a rough draft and i should have given Alk more room on the paper. Ill program a better visual in the future. This is a popular question, and this is roughly the approach i take to everything... look at a large batch of the collective data, bigger than this, and make my own assessment. Then through experience, modify my assessment over time.
Veterans, would you like for me to plot all your recommendations as well? It would be cool to get the collective ARC recommendations.
Charting out the ranges for folks- esp those starting out and new to the hobby or those having issues seems like a great idea! Having some sort of reference file for these sorts of things on the website would be super helpful I think to the membership!
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I have a 6-year going tank, with lots of SPS doing well, tons of LPS doing great, anemones great, fish great. All I *really* dose for and test is ALK. I found calcium does not change as much as ALK, and water changes kept it stable more or less. Every once in a while I test calcium and supplement if necessary. Got tired of dosing and testing mag. It never changed.
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