All For Reef Dosing Questions

Alex Dragon

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Nothing wrong with mag at 1100.. my tank runs there and it’s a full blown sps reef lol..
Maybe not for your tank, each tank is different, but my salt mixes at usually just over 1300+ magnesium if left unchecked my tank can consume to below 1200 in a week so I am trying to keep it above 1300 with dosing, a couple of my corals do seem to enjoy 1300+ and if its drops below 1200 they sulk and seem to die off i lost some but rescued another couple with raising it and keeping it above 1300 seems to very the sweet spot for my tank
 

Alex Dragon

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I’m not sure I’ve ever seen anything positive long term from less or no water changes. Very few who do no water changes document everything. Many don’t admit they are an above average reefer and their method does not and should not apply to the vast majority of hobbyists
Yes I am still looking into it all, but for now I will continue doing water changes just maybe less frequent than every week
 

Randy Holmes-Farley

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So can you tell me how much magnesium i need to use then off the 14.5ml daily dose of AFR to keep it at a safe level? Without doing some home testing?

Sure. If you have little coralline and most alk demand comes from hard corals, then you may need none.

If most of the alk demand comes from coralline algae, then AFR has about half of what I’d recommend.

All-For-Reef contains 43000 ppm calcium, Ca, 6000 dKH per liter alkalinity (as alkalinity-precursors), and 1900 ppm magnesium, Mg.

I recommend magnesium as 5-10% of the calcium. AFR has 4.4%.

Thus, I’d add another 5% if coralline is a big user. That means for each 1 mL of AFR (contains 43 mg of calcium), you would add an additional 2.2 mg of actual magnesium.

How much of a dose that is depends on what product you’d use.
 

rishma

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I assure you I read your posts. Just trying to help.

I’ll add one more post here to share information that you may find helpful now or perhaps in the future. It ties to the one @Randy Holmes-Farley just posted above and the previous comment by @twentyleagues

In reef tanks, the consumption of calcium, alkalinity, and magnesium happen in predictable proportions. For each 2.8 dKH of alkalinity consumed, about 18-20 ppm calcium and 1-2 ppm magnesium are also consumed.

All for Reef provides a little excess calcium to the ratio above and as Randy noted, just a hair lower on magnesium. Without any supplementation, or water changes, it would take quite a while for either the slightly rising calcium or slightly falling magnesium to become an issue. With water changes and a decent salt, I find both remain acceptable over the long term.
 

Alex Dragon

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I assure you I read your posts. Just trying to help.

I’ll add one more post here to share information that you may find helpful now or perhaps in the future. It ties to the one @Randy Holmes-Farley just posted above and the previous comment by @twentyleagues

In reef tanks, the consumption of calcium, alkalinity, and magnesium happen in predictable proportions. For each 2.8 dKH of alkalinity consumed, about 18-20 ppm calcium and 1-2 ppm magnesium are also consumed.

All for Reef provides a little excess calcium to the ratio above and as Randy noted, just a hair lower on magnesium. Without any supplementation, or water changes, it would take quite a while for either the slightly rising calcium or slightly falling magnesium to become an issue. With water changes and a decent salt, I find both remain acceptable over the long term.
Every single reef tank we create is individual and in that way no science will be totally accurate to the consumption of anything within them, AFR is giving us a baseline along with all the things in our tank salt mix equipment etc etc what we try and do in the hobby looking at all aspects is make things as stable as we can to make the inhabitants happy,
Small adjustments in all the things can be made to help.
And i agree the modern scientific way is good and helps a lot don't get me wrong and you can in some degree predict usage of all parameters and things you put in all stay the same Or similar but elements in our home aquarium isnt totally in our control we change things the environment around our tank changes, we add and take away corals and they grow fish grow etc etc so our water and elements inside it will constantly change maybe only in small ways, what we are doing in the hobby is trying to reduce large swings to make our inhabitants happy,
So if I see any of my inhabitants not looking happy over a period of time I look into things and to science to try and help them...
So I saw a change in corals and the only thing way off to what my salt mixes to is magnesium, and AFR for me like thousands of others am guessing isn't keeping up with the demand of my tank so I dose extra and it seems to be working for me and my tank... in the long term I will continue to look into new things to help,
Hence me coming here and posting asking about more magnesium consumption. And having people say it can't be doesn't work like that etc etc even though I read similar posts every single day.
I am just me doing my best to keep my aquarium occupants as happy and as stable as I can on a budget...
I appreciate help I do so thank you to people genuinely trying to help, but I will continue to listen to my home reef inhabitants
 
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Alex Dragon

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Sure. If you have little coralline and most alk demand comes from hard corals, then you may need none.

If most of the alk demand comes from coralline algae, then AFR has about half of what I’d recommend.

All-For-Reef contains 43000 ppm calcium, Ca, 6000 dKH per liter alkalinity (as alkalinity-precursors), and 1900 ppm magnesium, Mg.

I recommend magnesium as 5-10% of the calcium. AFR has 4.4%.

Thus, I’d add another 5% if coralline is a big user. That means for each 1 mL of AFR (contains 43 mg of calcium), you would add an additional 2.2 mg of actual magnesium.

How much of a dose that is depends on what product you’d use.
So according to the bottle 5ml per 10 ltr equates to 12.5ppm increase for every 10ltres of water
My tank volume is around 300ltr water roughly accounting for rock displacment etc and sump
Going off my home tests (maybe not so accurate as people say) but its the only things I have until I send sample for ICP testing.
Like I said in posts my salt mixes at 1300+ for mag which my tests do say is about right, I would like this to stay around that value, AFR alone after a day of consumption seems to drop below that hence I have been dosing additional. If I leave it for a few days I will see a drop of magnesium to around 1200 after a week its 1150 or so,
Initially before using AFR through water changes and and individual dosing of things I got the tank to its baseline figure around what my salt mixes too.
I started dosing minimum amount 15ml for 300ltr tank within days of starting my alk and calcium made minor swings so following the instructions I made small adjustments to afr dose and got to where my alk was around 8.8-8.9 ( a little higher than my salt mixes to at 8.2 alk) but that seems ok going off information/consumption, and calcium was around 420 which i about where my salt mix gives me,
But every time I test magnesium if I haven't dosed extra it drops every day so to me that tells me I need to dose extra to keep up with consumption and keep it around 1300,
I am trying a minimal dose of magnesium going off above information of 3ml a day currently,
That's where I am currently I will monitor and do test over the next few days weeks
PS I do have spots coralline etc but it isn't massive amounts
As i mentioned my AFR dose is 14.5ml a day
PPS I initially was using a premixed liquid AFR but swapped to powder version and mixed as per instructions stated. The levels between the premixed liquid and the powder did give slight minor difference in results btw but still resulted in magnesium depleting whilst alk calcium seemed about same within a few points
 
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Randy Holmes-Farley

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, I would like this to stay around that value, AFR alone after a day of consumption seems to drop below that hence I have been dosing additional. If I leave it for a few days I will see a drop of magnesium to around 1200 after a week its 1150 or so,

I think something is wrong in the testing or salinity.

There is no reef aquarium organisms that uses more more magnesium than about 1/10th of the calcium, and calcium cannot ever be consumed faster than 20 ppm for each 2.8 dKH of alk.

For you to have a drop in magnesium from 1300 to 1150 in a week is just not possible by consumption. It would require the addition of 1500 ppm of calcium and 210 dKH of alk during that week.
 

Alex Dragon

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I think something is wrong in the testing or salinity.

There is no reef aquarium organisms that uses more more magnesium than about 1/10th of the calcium, and calcium cannot ever be consumed faster than 20 ppm for each 2.8 dKH of alk.

For you to have a drop in magnesium from 1300 to 1150 in a week is just not possible by consumption. It would require the addition of 1500 ppm of calcium and 210 dKH of alk during that week.
Welcome to my dilemma..... where is my magnesium going?
My salinity is around 1.025-1.026 at most with ATO my tests are within tolerance of salt and LFS testing from 4 different sources I have checked against
 

Alex Dragon

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Welcome to my dilemma..... where is my magnesium going?
My salinity is around 1.025-1.026 at most with ATO my tests are within tolerance of salt and LFS testing from 4 different sources I have checked against
That drop was the most significant, I was dosing magnesium weekly, then I started twice a week and most recently daily, I generally test at the same time of day 8pm as lights are about to start to lower, my last AFR dose is 4pm, but from I have been told in this thread to maybe do one dose of AFR rather than 4 doses smaller doses idk if that may make a difference 🤷‍♂️
 

Randy Holmes-Farley

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Welcome to my dilemma..... where is my magnesium going?
My salinity is around 1.025-1.026 at most with ATO my tests are within tolerance of salt and LFS testing from 4 different sources I have checked against

Test error.
 

Randy Holmes-Farley

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My suggestion is to stop adding magnesium for a few weeks and just keep monitoring it. Keep using AFR and maintain alk with it. Don’t dose magnesium with every apparent drop.

There are no secret sinks for large amounts of magnesium.

I would check to be sure you do not have a low mag batch of salt.
 

Alex Dragon

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Ok I have ordered a new refractometer and also a new salinity calibration fluid to take the salinity out of the equation, and i will go from there and test the basics again when they arrive.
I will also re-do testing on my salt when I have calibrated to see if the batch has got issues, I only have salifert test for calcium, but I have salifert and hanna tester for alk so will do both on test batch of water when I have new refractometer,
I have also just double checked with a floating hydrometer in water am preparing and my current refractometer is slightly out Reading 1.023 so that could be giving wrong readings if only small.
As I say I will check again once I get the calibration fluid etc a post back on results in a few days
Thank you to all for input so far I will update when I have recalibrated my equipment
 

rtparty

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Ok I have ordered a new refractometer and also a new salinity calibration fluid to take the salinity out of the equation, and i will go from there and test the basics again when they arrive.
I will also re-do testing on my salt when I have calibrated to see if the batch has got issues, I only have salifert test for calcium, but I have salifert and hanna tester for alk so will do both on test batch of water when I have new refractometer,
I have also just double checked with a floating hydrometer in water am preparing and my current refractometer is slightly out Reading 1.023 so that could be giving wrong readings if only small.
As I say I will check again once I get the calibration fluid etc a post back on results in a few days
Thank you to all for input so far I will update when I have recalibrated my equipment

What salt are you using? Do you have a kitchen scale that can measure in grams?

Weighing your salt is a great way to test things since scoops and cups aren’t accurate measurements
 

Pod_01

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Ok I have ordered a new refractometer and also a new salinity calibration fluid to take the salinity out of the equation
I always struggled with refractometers, this really helped me with salinity:
1751168631539.jpeg

It works well although it is large…

Also what particular TMC salt do you use, I suspect TMC is Tropic Marin. They do have few salt types available… I use TM Pro Reef and so far no odd levels of Mg…

As for Mg, I tend to use ICP test results and make adjustments. At one point I had 3 different test kits and ended up with 3 different test results…

Good luck,
 

Alex Dragon

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I always struggled with refractometers, this really helped me with salinity:
1751168631539.jpeg

It works well although it is large…

Also what particular TMC salt do you use, I suspect TMC is Tropic Marin. They do have few salt types available… I use TM Pro Reef and so far no odd levels of Mg…

As for Mg, I tend to use ICP test results and make adjustments. At one point I had 3 different test kits and ended up with 3 different test results…

Good luck,
TmC is tropical marine centre salt and i have a hydrometer but not that particular one, I would normally calibrate about every 3 month, but looks like I fell off much quicker this time,
So I have another batch of calibration fluid coming to recalibrate everything
 

Miguel.PT

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Hey guys!

I've been manually dosing AFR, I'm now going to setup an automated system, and I'd like to make sure I'm using it as efficiently as possible. Perhaps I'm overthinking things, but I'm wondering if it would be better to dose however many mL all at once, or slowly throughout the day. Is there a better time of the day to dose AFR?

Thank you in advance for your help!
Id use it throught the day, im dosing it 5 times a day.
 

Pridedcloth3

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I been using it for year and it absolutely contains magnesium. Don't dose what your don't test for.

Screenshot_20250629_032942_Chrome.jpg
 
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