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Lou Ekus

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If you search R2R, you will find numerous threads where people dosing AFR and not adding extra magnesium run into issues with their corals and/or tank crashes. The mag in AFR isn't at dosing levels.
Each system runs very differently, especially in relation to Mg. They need to be monitored. Some will need extra, many will not. I don't agree with the statement that "many tanks using AFR crash due to the Mg in AFR not being at doeing levels"
 

Lou Ekus

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I find mag trends down over time with afr, I also dose dilute kalkwasser in my ato. I just dose an adjustment every 2-3 weeks. Usually adjust from 1260 up to around 1300 in one concentrated dose.
You are not getting the full benefit of the Mg in the AFR due to the Kalkwasser addition.
 

skey44

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You are not getting the full benefit of the Mg in the AFR due to the Kalkwasser addition.
I recognize this and saw your video comments on a brs talk too. I just see increased growth with very dilute kalk in my ato. 2.5 tsp/8ga. I previously ran my system without kalkwasser, afr only and had to dose magnesium similarly. AFR is the heavy lifter in my system. I use the same amount of afr with or without the kalk. The kalk drives the growth up and therefore I don’t have to adjust my afr dose when I add it to the top off.
I don’t mind dosing a little magnesium every other week, and I’d rather adjust up than down. Im a happy customer. Using TMPR salt religiously too.
 

RajM

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Am I song something wrong? I am up to 22ml on my 20g (13g of water) and I use only Cal as my proxy to dial in the dosing.
I do dose diy NoPox which I think eats a little bit of alk but over all my KH drifts between 7.9 and 8.3 daily.
I do dose AFR over a 24 hours in 12 doses right now.
My tank is SPS dominated and coraline is also taking off so I assumed that’s the main factor of it but when I read people dosing 10ml in 40g I am kinda worried.
 

Rhetoric

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Am I song something wrong? I am up to 22ml on my 20g (13g of water) and I use only Cal as my proxy to dial in the dosing.
I do dose diy NoPox which I think eats a little bit of alk but over all my KH drifts between 7.9 and 8.3 daily.
I do dose AFR over a 24 hours in 12 doses right now.
My tank is SPS dominated and coraline is also taking off so I assumed that’s the main factor of it but when I read people dosing 10ml in 40g I am kinda worried.
Consumption is based on demand, not water volume. Sounds like you've got a good routine thats working.
 

RajM

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As long as your alkalinity is staying in range you are good. Using a lot Just means you are successful and having a lot of growth.
Actually my Alk get used a bit more than my Cal. I keep an eye on my PH and if it goes below 7.9 I know my KH is out of balance and I test Alk and cal and do adjustment using BRS soda ash to bring it back to 8 dKH.
Usually my Cal is spot on and I only adjust using BRS Calcium Chlorides if it’s lower by 20ppm which is not very often. And then also adjust my AFR dose by 1ml.
 

Randy Holmes-Farley

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I personally recommend dosing AFR based on alk, not calcium, since calcium moves much more slowly from over or under dosing. But both can work.
 

RajM

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I personally recommend dosing AFR based on alk, not calcium, since calcium moves much more slowly from over or under dosing. But both can work.
How would you go about doing that? That’s what I did when I used ATI.

I thought since it’s calcium formate ( Ca(HCO2)2 ), Cal has to be used as proxy. Because until bacteria process the Ca(HCO2)2 you won’t see accurate alk reading of you dose. so at any given point of time you water will have KH from your salt mix, some of Ca(HCO2)2 and then KH from bacterial activity of processed Ca(HCO2)2.
Then if you do a waterchange you are removing some amount of each and adding more of what is in the salt mix.
 

twentyleagues

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How would you go about doing that? That’s what I did when I used ATI.

I thought since it’s calcium formate ( Ca(HCO2)2 ), Cal has to be used as proxy. Because until bacteria process the Ca(HCO2)2 you won’t see accurate alk reading of you dose. so at any given point of time you water will have KH from your salt mix, some of Ca(HCO2)2 and then KH from bacterial activity of processed Ca(HCO2)2.
Then if you do a waterchange you are removing some amount of each and adding more of what is in the salt mix.
This is one reason I dose all at once. Its usually testable in 24hrs. My alk does drift a bit throughout the day 8.5-9 but no corals seem worse for wear from it. I dose based on alk. If it falls below that range I bump up the dose if its a little higher I cut back a bit. Am I right? IDK but its working and easy so im good.
 

BriDroid

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This is one reason I dose all at once. Its usually testable in 24hrs. My alk does drift a bit throughout the day 8.5-9 but no corals seem worse for wear from it. I dose based on alk. If it falls below that range I bump up the dose if its a little higher I cut back a bit. Am I right? IDK but its working and easy so im good.
That’s how I do it too
 

Randy Holmes-Farley

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How would you go about doing that? That’s what I did when I used ATI.

I thought since it’s calcium formate ( Ca(HCO2)2 ), Cal has to be used as proxy. Because until bacteria process the Ca(HCO2)2 you won’t see accurate alk reading of you dose. so at any given point of time you water will have KH from your salt mix, some of Ca(HCO2)2 and then KH from bacterial activity of processed Ca(HCO2)2.
Then if you do a waterchange you are removing some amount of each and adding more of what is in the salt mix.

I would not use calcium, as I said. Just treat it like you are dosing kalkwasser, based on alk, but as folks note, don’t try to measure alk right after dosing.
 

gregrock68

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This is one reason I dose all at once. Its usually testable in 24hrs. My alk does drift a bit throughout the day 8.5-9 but no corals seem worse for wear from it. I dose based on alk. If it falls below that range I bump up the dose if its a little higher I cut back a bit. Am I right? IDK but its working and easy so im good.
This is how I dose one of my tanks as well. Very simple and very effective, just make micro adjustments based on the dkh test. Cal seems to hang anywhere from 410 to 435 anytime I test it
 

SFNanoReef

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I also dose AFR based on my dKH. Personally, I believe maintaining stable alkalinity (around 8–9 dKH) is more important than worrying too much about slight calcium and magnesium drift. I’m currently using a Kamoer F4 (thanks to a fellow R2R member!) with AFR dosed at 0.5ml every hour, 24/7. The other three pumps are set up for alkalinity, calcium, and magnesium to make minor adjustments as needed.

Oh, and it’s a small 24g mixed nano tank—probably closer to 20 gallons after displacement. Unfortunately, my current bucket of Reef Crystals has been killing me with magnesium testing at 1020 ppm. I end up having to dose a ton of magnesium to the mix before it even goes into the tank.

Time to switch salts?
 

rishma

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Each system runs very differently, especially in relation to Mg. They need to be monitored. Some will need extra, many will not. I don't agree with the statement that "many tanks using AFR crash due to the Mg in AFR not being at doeing levels"
Lou- “I don’t agree…” was a very diplomatic response to an absolute false statement.

AFR provides plenty of Mg in my experience and most others.

Not to mention the idea of any tank “crashing” due to low Mg is hard to believe. If people are not using a supplement like AFR that adds magnesium, I think anemic growth is the more probable downside.
 
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Alex Dragon

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Hi, I am currently dialing in my 300ltr+ mixed reef with AFR went to recommend dose and got too much alk and not enough calcium so dosed calcium and reduced dose to 14.5ml which seems to have settled after 10days at 8.8alk and around 430 calc, but am also dosing 5ml of magnesium(salifert) pretty much everyday just to keep it above 1300, would this be about right to you folks?
I dose in early part of day just before lights come on but split it into 4 smaller doses over the start of light cycle
 

rishma

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Hi, I am currently dialing in my 300ltr+ mixed reef with AFR went to recommend dose and got too much alk and not enough calcium so dosed calcium and reduced dose to 14.5ml which seems to have settled after 10days at 8.8alk and around 430 calc, but am also dosing 5ml of magnesium(salifert) pretty much everyday just to keep it above 1300, would this be about right to you folks?
I dose in early part of day just before lights come on but split it into 4 smaller doses over the start of light cycle
Does not sound right to me.

AFR cannot under dose calcium if you are maintaining alkalinity.

I think it’s unlikely you need to dose much magnesium. It’s possible if you have very heavy coraline growth.

I just test alkalinity, dose AFR, and do an ICP once or twice a year. Keeps everything in range.

I find home calcium tests somewhat inconsistent. Home Magnesium tests are generally unreliable and Randy recommends against testing at home due to inaccuracy.
 

Alex Dragon

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Does not sound right to me.

AFR cannot under dose calcium if you are maintaining alkalinity.

I think it’s unlikely you need to dose much magnesium. It’s possible if you have very heavy coraline growth.

I just test alkalinity, dose AFR, and do an ICP once or twice a year. Keeps everything in range.

I find home calcium tests somewhat inconsistent. Home Magnesium tests are generally unreliable and Randy recommends against testing at home
Sorry but your information doesnt seem correct to me, did you read my post?
AFR can indeed fluctuate between alk and calcium especially while setting it up and all AFR tells you this in all there information, and lot of other uses have also told me this, and it takes time to settle but everytime you change something or add more load to the tank (mainly corals etc and the general forming or algae and coralline etc you need to compensate with dosing or if vast change is present you do indeed need to dose 1 or the other to compensate..... magnesium is the tricky one I am trying to dial in as well of thousands of others that have similar issues with larger magnesium using tanks that AFR alone can't keep up with...
 

twentyleagues

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Sorry but your information doesnt seem correct to me, did you read my post?
AFR can indeed fluctuate between alk and calcium especially while setting it up and all AFR tells you this in all there information, and lot of other uses have also told me this, and it takes time to settle but everytime you change something or add more load to the tank (mainly corals etc and the general forming or algae and coralline etc you need to compensate with dosing or if vast change is present you do indeed need to dose 1 or the other to compensate..... magnesium is the tricky one I am trying to dial in as well of thousands of others that have similar issues with larger magnesium using tanks that AFR alone can't keep up with...
AFR is a bit heavy on calcium its not balanced so with typical use you could see an increase in calcium over time if nothing else is done like water changes with lower than your current level of calcium. Kalkwasser is the same. This is what I think @rishma was talking about. This does not explain what is going on with your situation could be precipitation or just inaccuracy in test.

I also feel that splitting up your small dose is just delaying the delay and not needed or possibly wanted.
 

Alex Dragon

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sorry @twentyleagues but did you read my post? It's only been 2 week since starting AFR and clearly in AFR instructions on all the sites says it tells you to adjust add alk/calcium till stable and or increase/decrease afr till stability is reached, which is what I have done/doing..... it is my magnesium that isn't stable anyway..... I have to dose that extra daily on top of afr just to keep it above 1300....
 
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