Balancing Alkalinity and Ca

DrGiga

Community Member
View Badges
Joined
May 6, 2021
Messages
25
Reaction score
30
Location
Albany NY
Rating - 0%
0   0   0
Hi All,
I have a 209G reef tank ( 10 years old) and use BRS 2-parts dosing of soda ash and and Ca chloride mix. I also dose Mg. I use trident analyzer to monitor all 3 parameters daily and control dosing. I can not get Alk and Ca stabilized. Alk goes high but Ca reduces. Then I stop dosing and then Ca goes crazy high and Alk drops. I have attached the trident results below. When I got Alk stabilized around 9.6 dkH then ca dropped to about 340. I checked calibration of trident against multiple other tests and numbers are OK.
Initially I was dosing about 50 ml Ca and 50 ml Soda ash and 50 ml Mg then I tried 70 ml daily . No matter what I do I can not get these stabilized. Due to this stress I lost many SPS colonies. I would appreciate any help or advice. Thanks
Tank size 210 g., Salinity 35 ppm, mainly SPS but very few left. I also use Carbon dosing. dose Vodka 18 ml per day.
My nitrite and Phosphate are high due to high feeding. Nitrite 10 ppm, Phosphate 1 ppm.
I have about 20 fish and feed them 5 cubes per day.

Alk_Ca.PNG Alk_Mg.PNG Alk_Ca_low.PNG
 

JCM

Valuable Member
View Badges
Joined
Jan 28, 2018
Messages
1,342
Reaction score
1,646
Rating - 0%
0   0   0
You don't have to dose equal amounts of calcium and soda ash. Get your ALK stable, then dose enough calcium to keep it stable.

1 ppm phosphate? That's 10x the recommended upper limit. You're feeding too much.
 
OP
OP
D

DrGiga

Community Member
View Badges
Joined
May 6, 2021
Messages
25
Reaction score
30
Location
Albany NY
Rating - 0%
0   0   0
You don't have to dose equal amounts of calcium and soda ash. Get your ALK stable, then dose enough calcium to keep it stable.

1 ppm phosphate? That's 10x the recommended upper limit. You're feeding too much.
Thank you for feedback. However, BRS recommends to use the same volume of their mix for both Ca and Alkalinity. Here is my latest Alkalinity and and Ca. I have not dose the tank in the last 3 or 4 days. Ca continue to go up and Alkalinity continue to drop. This tank was stable for years. then I put it on automatic dosing with trident and it worked very well for few months, but then it seems that somehow tank went out of control. I do believe the trident measurements are reliable however automatic dose control seems to be an issue.
2 weeks ago I tried to correct for Alkalinity and it temporary increased but then again alkalinity started to drop and Ca increased.
Considering Phosphate, I know it is high as I stopped GFO. but I am setting up chaeto refugium that I hope to bring it down.
I really appreciate further comments for controlling Alkalinity and Ca. I am afraid if I increase Alkalinity it results in further increase of Ca. Any suggestions?
 

Attachments

  • Alk_Ca_May16.PNG
    Alk_Ca_May16.PNG
    54.2 KB · Views: 33

monkeyCmonkeyDo

7500 Club Member
View Badges
Joined
Mar 4, 2019
Messages
8,288
Reaction score
8,087
Location
Puyallup, Wa USA
Rating - 0%
0   0   0
Do a wc. Restore balance.
Stop dosing. Monitor ur alk.
I dont care if brs says to use equal parts of this or that. Lol.
Not all tanks are the same.
Why dose the calcium if its not needed?
Re evaluate ur alk upkeep.
Than do another small wc to bring cal and mag back. Ur alk will be good so watch cal every other day and start dosing accordingly. Check 1hr after dose. See ur numbers and what your dose does. Hths you.
D
 

jassermd

Well-Known Member
View Badges
Joined
Oct 22, 2020
Messages
573
Reaction score
810
Location
Southlake
Rating - 0%
0   0   0
You are dealing with an issue that is likely avoidable...
I have the Trident and agree... the readings are reliable... most of the time.
I've had readings within 15 min of each other on ALK vary by more than 1.5dKH and Ca by more than 75 ppm. In every case, it was an aberrant reading. I double check with Hanna and confirm.

I too have DOS's and capability of doing auto dosing. However, there is no way I would do it! I get at least 1-2 aberrant readings from Trident due to debris, air bubble, etc that messes with the accuracy of the measurement at least 1x per week. One of my fellow reefers has a similar set up and tried to do the auto controlled dosing. He's having the same issues you are eluding to.
When it comes to the chemistry of my tank, I don't trust anyone or any technology to auto dose based on readings that can be aberrant or erroneous.
You may want to stop with the controlled dosing and use your intuition to dose based on consumption. You can always reconfirm your readings if they are off before a dose is given...
I've personally seen too many erroneous readings to feel comfortable with auto dosing!
Just my 2 cents.
 
OP
OP
D

DrGiga

Community Member
View Badges
Joined
May 6, 2021
Messages
25
Reaction score
30
Location
Albany NY
Rating - 0%
0   0   0
All,
Here is my attempt to increase Alkalinity. I manually added Soda ash to the tank, Alkalinity increased but the Calcium sky rocketed. At the same time, Magnesium dropped.
Any idea what is going on?

1621360201964.png

1621360352794.png
 

ReefHomieJon

Well-Known Member
View Badges
Joined
Sep 5, 2019
Messages
909
Reaction score
1,075
Location
Lake Elsinore
Rating - 0%
0   0   0
You don't have to dose equal amounts of calcium and soda ash. Get your ALK stable, then dose enough calcium to keep it stable.

1 ppm phosphate? That's 10x the recommended upper limit. You're feeding too much.
Either feeding too much or maybe just needs to up his export methods
 

Randy Holmes-Farley

Reef Chemist
View Badges
Joined
Sep 5, 2014
Messages
66,553
Reaction score
62,861
Location
Arlington, Massachusetts, United States
Rating - 0%
0   0   0
All,
Here is my attempt to increase Alkalinity. I manually added Soda ash to the tank, Alkalinity increased but the Calcium sky rocketed. At the same time, Magnesium dropped.
Any idea what is going on?

1621360201964.png

1621360352794.png

Calcium cannot rise like that without dosing it. Dosing alkalinity does not make it rise (or fall much either).

Might be a testing problem, or maybe you have the dosing solutions confused.
 

Doctorgori

2500 Club Member
View Badges
Joined
Mar 18, 2019
Messages
4,132
Reaction score
5,389
Location
Myrtle Beach
Rating - 0%
0   0   0
yup I just zapped a tankful of developing frags thinking my Trident gizmo could do it for me. Just asking but with all the deaths and such is the tank back within the stone age realm of kalkwasser dosing? I mean just to simplify, stabilize and get you back on yer feet? that’s what I’m doing now that half my tank is dead jacking around with human error and Tridents et.
 

twwety

Community Member
View Badges
Joined
Dec 7, 2013
Messages
75
Reaction score
98
Rating - 0%
0   0   0
A high or low reading will only adjust your dosing by 10%(by default) and reading to high or low wont adjust it all and will send you a warning.
 

blasterman

Valuable Member
View Badges
Joined
Feb 14, 2019
Messages
1,730
Reaction score
2,018
Rating - 0%
0   0   0
As per the other suggestions *STOP* locking calcium and alkalinity together and deal with each individually. Alk first. Next, stop worrying about magnesium. It's depleted at a fraction the rate of calcium.

Alk goes down, never up....sometimes down very fast, but it always goes down, and it doesn't have to be in step with calcium. This is either a testing error or instrument error.

Calcium is less variable than alk and minor calcium variances don't bother corals.

As usual, BRS is creating more problems than helping.
 
OP
OP
D

DrGiga

Community Member
View Badges
Joined
May 6, 2021
Messages
25
Reaction score
30
Location
Albany NY
Rating - 0%
0   0   0
Randy and All,
Thank you for your suggestions. I really enjoyed reading Randy's papers on chemistry of the Reef keeping. Thank you Randy for your continuing support to this community.
I think that trident will read correct values. Yesterday I dosed tank to increase Alkalinity by 1dkH. As you see from the graph above the Alkalinity has increased very close to 1 dKH. Considering sources of errors in dosing it seems that Trident has done a very good job in measuring Alkalinity.
Today, I will check these values again by Red Sea test kit and Hana test kit to verify instrument reliability.
Considering mixing up of my dosing solutions, it is unlikely, but I will verify. I usually prepare 5 gallon of the chemical mix at a time and have done this for more than 10 years and have not had an issue before, but will verify that I have correct solutions in the dosing containers. Probably checking pH or observing change of color when I add soda ash to the tank is the easiest way.
I plotted Ca (orange) and Mg (blue). It seems that increase of Ca happens with reduction of Mg. Does this means that Ca got released from Mg back into the water. Ca continue climbing up (>760 ppm??) without any dosing of any chemical in the tank except Vodka ( 10 ml for 210 gallons)
I am going to do partial water change and will keep you updated.
1621436106888.png
 

jurgenph

Well-Known Member
View Badges
Joined
Jul 9, 2018
Messages
602
Reaction score
679
Rating - 0%
0   0   0
i can't speak to what is going on... but i'd like to say, your calcium levels of 550 - 770 seem unnaturally high.
could that be a contributing factor?


J.
 

Mastering the art of locking and unlocking water pathways: What type of valves do you have on your aquarium plumbing?

  • Ball valves.

    Votes: 71 53.0%
  • Gate valves.

    Votes: 68 50.7%
  • Check valves.

    Votes: 34 25.4%
  • None.

    Votes: 30 22.4%
  • Other.

    Votes: 9 6.7%
Back
Top