Low Alk! Can't get it to increase

[WallysWorld]

I found this in the Red Sea Manual for their Foundation Elements:

"Causes and effects of unbalanced levels of foundation elements

• New aragonite substrate - new aragonite surfaces can increase the non-biological precipitation of calcium and carbonates which will lead to their depletion from the water, causing a drop in calcium and alkalinity."​

When I started my tank I used dry bulk saver reef rock. So this could be "New Aragonite" and the cause of non-biological precipitation. Calcium is also being consumed, but not to the same amounts.

I'm on day three of smaller doses three times a day (thank god my partner comes home for lunch). Total 24 hour dose is 15 ml Foundation B (Alk), and 5 ml Foundation A (Ca+). Latest test parameters:

Alk - 8.1 dKH
Ca - 420 ppm
Mg - 1380 ppm​

Looks like dosing smaller amounts multiple times in a day is the solution. I just bought a doser!

 

[McPikie]

I'd also go with mixing up your own. It's far cheaper in the long run. If you want to keep your Kh at 11 as per the bucket of salt, then I would buffer the tank up to 11 using the widely available calculators, then dose no Kh supplement for 4 days and retest again. This will give you your daily drop and then work out from there.

 

[Reef of Fillory]

@WallysWorld

Just as a reference, there are some cheap dosing pumps which a good number of people use. They aren't necessarily the most accurate in dosing amounts, but I have successfully used them in the past.

4 head: https://www.amazon.com/Jebao-Progra...ocphy=9017437&hvtargid=pla-355499729753&psc=1

2 head: https://www.chewy.com/jebao-multi-c...vk59u8U6D2GhvkePV5CO4aIfyHadsH1RoC4hoQAvD_BwE



IMO I would get your ALK to your desired value, and then don't dose/test for two days. Run everything normally, then after 2 days [48 hours after the initial test + dose] run another test, divide the difference by two and that is your starting ALK dose. When you make large changes [add multiple corals, growth of coraline or frags has accelerated] Revisit your daily dosage by testing 24 hours apart. If your ALK has dropped in this period, up your dosage by the appropriate amount to adjust back to your baseline. This is the way that I figure/adjust my dosing throughout time on my tank.

 

[lapin]

To play devil's advocate, what would be using up carbonate like that in a new tank? Stony corals, tridacna clams, coralline algae - What else incorporates a significant amount of carbonate as it grows?

Whats growing, I do not know. It was my experience with my past 2 tanks. After filling with water and a few weeks of stable Alk, I experienced a steady drop over 4 weeks time. My thinking was something that started growing was using it up. If it was precipitation, I never saw it with my eyes. Never coated any surfaces I could see. However I found this info and will do some more research:
Red Sea says
"Causes and effects of unbalanced levels of foundation elements
• New aragonite substrate - new aragonite surfaces can increase the non-biological precipitation of calcium and carbonates which will lead to their depletion from the water, causing a drop in calcium and alkalinity"

Another arcticle I found by Randy, saying both can occur. However the link to the biological info is broken.
http://www.reefkeeping.com/issues/2002-04/rhf/feature/index.php

 

[WallysWorld]

@WallysWorld

Just as a reference, there are some cheap dosing pumps which a good number of people use. They aren't necessarily the most accurate in dosing amounts, but I have successfully used them in the past.

4 head: https://www.amazon.com/Jebao-Progra...ocphy=9017437&hvtargid=pla-355499729753&psc=1

2 head: https://www.chewy.com/jebao-multi-c...vk59u8U6D2GhvkePV5CO4aIfyHadsH1RoC4hoQAvD_BwE



IMO I would get your ALK to your desired value, and then don't dose/test for two days. Run everything normally, then after 2 days [48 hours after the initial test + dose] run another test, divide the difference by two and that is your starting ALK dose. When you make large changes [add multiple corals, growth of coraline or frags has accelerated] Revisit your daily dosage by testing 24 hours apart. If your ALK has dropped in this period, up your dosage by the appropriate amount to adjust back to your baseline. This is the way that I figure/adjust my dosing throughout time on my tank.

Thanks for the recommendations on dosing pumps, and advice. I bought this Dosing Pump:

https://www.reefbreeders.com/shop/coral-box-wifi-dosing-pump/

It's slightly smaller than the Jebao, and doesn't have buttons on top which allow me to mount it up out of the way in my small cabinet. The pump heads look surprizingly similar to those on the Jebao, but then maybe everyone is simply OEM'ing these heads.....

 

[Reef of Fillory]

Thanks for the recommendations on dosing pumps, and advice. I bought this Dosing Pump:

https://www.reefbreeders.com/shop/coral-box-wifi-dosing-pump/

It's slightly smaller than the Jebao, and doesn't have buttons on top which allow me to mount it up out of the way in my small cabinet. The pump heads look surprizingly similar to those on the Jebao, but then maybe everyone is simply OEM'ing these heads.....

Much nicer dosing pump than the Jebao - good choice. I always like to show people that there are budget options in case they're debating between not having a dosing pump and hand dosing every day. That almost never works out. I also don't do water changes on my tank, and prefer to rely on dosing for renewing major element levels rather than the sways of renewal via water change.

 

[WallysWorld]

Whats growing, I do not know. It was my experience with my past 2 tanks. After filling with water and a few weeks of stable Alk, I experienced a steady drop over 4 weeks time. My thinking was something that started growing was using it up. If it was precipitation, I never saw it with my eyes. Never coated any surfaces I could see. However I found this info and will do some more research:
Red Sea says
"Causes and effects of unbalanced levels of foundation elements
• New aragonite substrate - new aragonite surfaces can increase the non-biological precipitation of calcium and carbonates which will lead to their depletion from the water, causing a drop in calcium and alkalinity"

Another arcticle I found by Randy, saying both can occur. However the link to the biological info is broken.
http://www.reefkeeping.com/issues/2002-04/rhf/feature/index.php

I just got time to start reading this article....great reference.....I need to do more studying! Thanks

 

[rkpetersen]

• New aragonite substrate - new aragonite surfaces can increase the non-biological precipitation of calcium and carbonates which will lead to their depletion from the water, causing a drop in calcium and alkalinity."​

Any hard clumped areas in your sandbed?

\

I think you've hit the nail on the head here. And this is what I was thinking of when I made that comment about the sandbed earlier. It is possible to precipitate so much additional calcium carbonate into your sand that it becomes hard, like limestone rock.

Glad that the divided dosing is working! Dosers are the way to go; imo LFSs should at least discuss them with new hobbyists right off the bat or at least pretty soon thereafter.

 

[cracker]

I also was puzzled by the disappearing alk trick. Until I realized my sand bed was rocking up in some places. So I now to more, smaller doses.