How do I raise alkalinity without raising magnesium and calcium.

[dnprall]

Hello!

I'm using Tropic Marin All-for-Reef for dosing calcium/alkalinity and I know it has magnesium in it. Since the tank has been new, my alkalinity has been in the low 7's. When I started using the All-for-Reef per the bottle instructions, it seemed to swing calcium and magnesium quite high but not a big alkalinity increase so I've back off on dose and frequency.

At this time, I'm using small amounts of All-for-Reef and trying to keep calcium and magnesium from having large swings. Yesterday, my calcium was 379 and magnesium was 1310 and alkalinity was 7.4.

I'd like to increase the alkalinity to the high 7s/low 8s without increasing the calcium and magnesium with sharp swings. There is so much information on this website that I'm finding it hard to assimilate/synthesize what I should be doing.

Should I be using soda ash?

Thanks!

 

[Randy Holmes-Farley]

You can use baking soda/sodium bicarbonate, washing soda/soda ash/sodium carbonate, or sodium hydroxide. They are listed in oder of increasing pH boost per unit of alk added.

That said, you should want to boost calcium and I'd use All For Reef for any alk additions you need in the near term. Calcium and amgnesium wuill not bounce around too much.

 

[dnprall]

Perfect. That's what I need to know Randy. I'm comfortable with All-for-Reef. Very much appreciate your help.

Now on to figuring out the kinetics of my tank regarding phos dosing

 

[Icryhard]

You can use baking soda/sodium bicarbonate, washing soda/soda ash/sodium carbonate, or sodium hydroxide. They are listed in oder of increasing pH boost per unit of alk added.

That said, you should want to boost calcium and I'd use All For Reef for any alk additions you need in the near term. Calcium and amgnesium wuill not bounce around too much.

For some odd reason my magnesium is going up when adding baking soda. I honestly have no idea as to how, since there shouldn't be any magnesium present. Any other reason this could be happening? I do not add anything aside from amino and stuff like that for the corals.

 

[Randy Holmes-Farley]

For some odd reason my magnesium is going up when adding baking soda. I honestly have no idea as to how, since there shouldn't be any magnesium present. Any other reason this could be happening? I do not add anything aside from amino and stuff like that for the corals.

Test error is the only possibility, assuming you added sodium bicarbonate, and is very common for magnesium.

 

[Garf]

Or increasing salinity

 

[Randy Holmes-Farley]

Or increasing salinity

Yes.

 

[Joe.D]

Old thread, but pertinent to my situation. I got to the bottom of my dosing reservoir of All for Reef and there was some calcium precipitate and it must’ve dosed much higher levels of calcium. I went from around 420 ppm Ca to somewhere over 550 to 600 - the Red Sea kit tops out at 500, but I went beyond and added more and I’m thinking am close to 600.

I turned off my All for Reef dosing and Ca has come down slightly, but my Alk is now 7.2.

Was searching on how to raise Alk without raising Ca and came across this thread.

My total system volume is approx 95 gallons - 75 display and 20 sump.

@Randy Holmes-Farley, What’s the best way to go about adding baking soda and how much to add to raise Alk?

 

[Randy Holmes-Farley]

Old thread, but pertinent to my situation. I got to the bottom of my dosing reservoir of All for Reef and there was some calcium precipitate and it must’ve dosed much higher levels of calcium. I went from around 420 ppm Ca to somewhere over 550 to 600 - the Red Sea kit tops out at 500, but I went beyond and added more and I’m thinking am close to 600.

I turned off my All for Reef dosing and Ca has come down slightly, but my Alk is now 7.2.

Was searching on how to raise Alk without raising Ca and came across this thread.

My total system volume is approx 95 gallons - 75 display and 20 sump.

@Randy Holmes-Farley, What’s the best way to go about adding baking soda and how much to add to raise Alk?

I'd seriously look at calcium test error rather than overdosing. I don't see a way AFR boosts calcium by >100 ppm without alk going up by more than 10 dKH.

 

[Joe.D]

Good point. I did get a new reagent refill kit and that coincided with the spike and I’ve tried retesting after water change and got similar results. I took a water sample to my LFS and they came in a bit lower than my new test kit, but still higher than normal.

I sent a note to BRS asking to replace the refill kit thinking maybe it was a bad set of reagents and haven’t heard back yet.

You thinking I should go back to dosing All for Reef and assuming bad test kit? What’s the down side of running Ca on the high side? Won’t any excess Ca get used by the corals eventually?

 

[Randy Holmes-Farley]

Good point. I did get a new reagent refill kit and that coincided with the spike and I’ve tried retesting after water change and got similar results. I took a water sample to my LFS and they came in a bit lower than my new test kit, but still higher than normal.

I sent a note to BRS asking to replace the refill kit thinking maybe it was a bad set of reagents and haven’t heard back yet.

You thinking I should go back to dosing All for Reef and assuming bad test kit? What’s the down side of running Ca on the high side? Won’t any excess Ca get used by the corals eventually?

Could be the old testing was bad and the new one is OK.

AFR will very slowly raise calcium relative to alk.

Maintaining alk (say, baking soda) while dosing no AFR will allow calcium to decline, though 550 ppm is also OK.

 

[Joe.D]

Could be the old testing was bad and the new one is OK.

AFR will very slowly raise calcium relative to alk.

Maintaining alk (say, baking soda) while dosing no AFR will allow calcium to decline, though 550 ppm is also OK.

Gotcha - thanks

 

[helwrj28]

You can use baking soda/sodium bicarbonate, washing soda/soda ash/sodium carbonate, or sodium hydroxide. They are listed in oder of increasing pH boost per unit of alk added.

That said, you should want to boost calcium and I'd use All For Reef for any alk additions you need in the near term. Calcium and amgnesium wuill not bounce around too much.

Would you mind sharing a calculator for these products?

I'm thinking of making something instead of overpaying for the same products! Thanks

 

[Randy Holmes-Farley]

Would you mind sharing a calculator for these products?

I'm thinking of making something instead of overpaying for the same products! Thanks

Reef Chemistry Calculator

reef.diesyst.com

We have loads of DIY recipes if you want them.

 

[helwrj28]

Reef Chemistry Calculator

reef.diesyst.com

We have loads of DIY recipes if you want them.

Thank you!

 

[Luky]

I am having similar issues with low Alk while using All For Reef. I started dosing it April 2023 at 8.5ml/day based on a bunch of testing and watching my calcium consumption. It's a 65gal tank with another 5 gal in the sump. I had increased to 10ml/day after 4-5 months as I noticed my alkalinity would go below 8 with my ph being around 8 to 8.1. Calcium 400+/-20 and magnesium 1300 +/-50. I would add some Kent superbuffer dKh (not made anymore) to bring it up, which also jumped up the calcium. A few months ago I bumped the dosing up to 12ml/day. I do 17 gal water changes every 1-2 weeks with Scripps (filtered) sea water and have a RODI ATO to maintain salinity at 1.024-1.025.

I had not tested Alk since 4/8/24 as I ran out of hanna reagent. I just got some new stuff and tested the Alk last Friday and found it was only 6.2-6.3 (tested twice), but everything else was within my typical normal range. (Nitrates 12.9/phos 0.23 which I keep on the high side as I have had issues with dinos when I got my levels too low). Filtration is a rollermat and a DC skimmer. Chiller maintains 76F temp.

I had a about 2 tsp left of the Kent Superbuffer that I added Friday before we went out of town and last night (Sun) I added 1tsp baking soda based on the calculator (linked above). I retested today (Monday) and Alk is at 8.3 dKh.

I find it curious that others are also seeing issues with low Alk while dosing AFR. I wonder how widespread this is? I have read that Tropic Marin had issues previously with other products (salt?) Maybe their quality control on their chemical mixing is not so good to maintain consistency thoughout a batch? I have been using the same 800g container to make my AFR 500ml at a time (using 0.1g balance to weigh out 500g/ml RODI water and 80g powder). My first 800g AFR batch is almost gone and I will have to get a new cannister in the next month or two.

 

[Randy Holmes-Farley]

I am having similar issues with low Alk while using All For Reef. I started dosing it April 2023 at 8.5ml/day based on a bunch of testing and watching my calcium consumption. It's a 65gal tank with another 5 gal in the sump. I had increased to 10ml/day after 4-5 months as I noticed my alkalinity would go below 8 with my ph being around 8 to 8.1. Calcium 400+/-20 and magnesium 1300 +/-50. I would add some Kent superbuffer dKh (not made anymore) to bring it up, which also jumped up the calcium. A few months ago I bumped the dosing up to 12ml/day. I do 17 gal water changes every 1-2 weeks with Scripps (filtered) sea water and have a RODI ATO to maintain salinity at 1.024-1.025.

I had not tested Alk since 4/8/24 as I ran out of hanna reagent. I just got some new stuff and tested the Alk last Friday and found it was only 6.2-6.3 (tested twice), but everything else was within my typical normal range. (Nitrates 12.9/phos 0.23 which I keep on the high side as I have had issues with dinos when I got my levels too low). Filtration is a rollermat and a DC skimmer. Chiller maintains 76F temp.

I had a about 2 tsp left of the Kent Superbuffer that I added Friday before we went out of town and last night (Sun) I added 1tsp baking soda based on the calculator (linked above). I retested today (Monday) and Alk is at 8.3 dKh.

I find it curious that others are also seeing issues with low Alk while dosing AFR. I wonder how widespread this is? I have read that Tropic Marin had issues previously with other products (salt?) Maybe their quality control on their chemical mixing is not so good to maintain consistency thoughout a batch? I have been using the same 800g container to make my AFR 500ml at a time (using 0.1g balance to weigh out 500g/ml RODI water and 80g powder). My first 800g AFR batch is almost gone and I will have to get a new cannister in the next month or two.

Low alk when using AFR simply means you are not using enough.

 

[Luky]

Is that true if all of my other parameters are inline with targeted norms that have been pretty stable for a year? If I increase AFR from 12ml to 20ml/day won't that overly increase my calcium/magnesium/Ph etc.? Is there a downside to "over dosing" AFR other than higher cost? Since the true nutrient levels don't show up for days until they are chemically converted, I am cautious about overdoing my dosing.

Is there a calculator for suggesting how much to increase my daily AFR dosing? Not sure if that is possible as each tank would have a different uptake of nutrients based on animal composition/bio load.

Thank you for your feedback.

 

[Randy Holmes-Farley]

Is that true if all of my other parameters are inline with targeted norms that have been pretty stable for a year? If I increase AFR from 12ml to 20ml/day won't that overly increase my calcium/magnesium/Ph etc.? Is there a downside to "over dosing" AFR other than higher cost? Since the true nutrient levels don't show up for days until they are chemically converted, I am cautious about overdoing my dosing.

Is there a calculator for suggesting how much to increase my daily AFR dosing? Not sure if that is possible as each tank would have a different uptake of nutrients based on animal composition/bio load.

Thank you for your feedback.

Yes, my statement is correct regardless of any other levels. If you try to keep alk higher by 2.8 dKH, calcium will only rise by 20 ppm and the magnesium rise will be undetectable.

There's no calculator that can tell you how much is needed to maintain levels, unless you independently know your daily alk demand.

I'd just use 50% more AFR for a while and track alk over a week.

There's no significant drawback to higher doses except cost, and the fact that pH may be higher if you use alternatives that raise pH.

 

[Luky]

Hello Randy, one more question on dosing AFR please? I increased my AFR dosing from 12ml to 20ml per day per your input and will monitor my level and adjust the daily AFR to get it to hold around 9 dKh.

The question is the best way to dose? Right now I am doing the entire amount once per day, releasing it into my sump near to the return pump intake (which is same chamber as the skimmer). I do have the ability to schedule more doses of lesser quantity if that would be better? I noted in my testing of the dosing pump (Kamoer F1 BT pump) that there was some level of error when dispensing into a graduated cylinder (informal GR&R study). It seemed like I could minimize the total dosing variation by doing a single daily dose vs say 10 times a day x 2ml per dose.