Amount of 2 Part to Dose???

[Salt1972]

We recently started monitoring / maintaining Alkalinity, Calcium, & Mag on our 125g mixed reef. Tank was started in September 2017 and has a large colony of Duncans and a large colony of FrogSpawn in addition to a few frags of GSP, Red Setosa, Torch, and a couple of Zoas. From reading, I would have guessed this is a "light" load tank.

Effort #1 - Kalkwasser in ATO.
A. Mix #1 - 1 tsp/g -- Couldn't tell Kalk was doing anything after a week. Supplementing with Red Sea - Alk / Ca

B. Mix #2 - 2 tsp/g -- Barely any indication Kalk was supplementing dKH. Alk depletion even with Kalk was a consistent 1.4 dKH / day. Supplement with 70mL Red Sea Alk daily.

Effort #2 - BRS 2 Part -- Yesterday, we mixed the Alkalinity, Calcium, & Mag supplements. The suggested dosing amounts ranged for .1mL/g - .3mL/g depending on LPS, SPS, or SPS Dominant... For a 125g system, that equates to 12.5 - 37.5mL/day. Well, day #1 (still using 2tsp/g Kalk in ATO) - demand is 1.4dKH. That meant dosing 90mL.

That's 2.5 - 7 times the recommended dosage. What am I missing? I'm concerned we're doing too much. Why would our "light load" tank be requiring so much alkalinity supplement?

Thanks in advance.

 

[Randy Holmes-Farley]

What alkalinity are you trying to maintain? The higher the target the more it takes each day.

 

[Salt1972]

What alkalinity are you trying to maintain? The higher the target the more it takes each day.

10dKH

 

[Randy Holmes-Farley]

I’m not sure how you are calculating the dose, but 1.4 dKH per day at 10 dKH is not excessive. Coralline alone can use more than that. That said, you can certainly dose less and let the alk decline somewhat if you want.

 

[Salt1972]

I’m not sure how you are calculating the dose, but 1.4 dKH per day at 10 dKH is not excessive. Coralline alone can use more than that. That said, you can certainly dose less and let the alk decline somewhat if you want.

Randy- Thank you very much for your continued help. My concern stems from being so far above the suggested range. Without experience / exposure, all we can do is compare to published norms. If we're doing the right thing, we appreciate the confirmation. If not, we're hoping to hear suggested actions.

Again, thank you for your time and counsel.

M

 

[Chiefmaster30]

Just Out of curiosity: when you dose the alk part are you dosing the calcium part in equal amounts? If not you could be chasing numbers like I done couple months back.

 

[Randy Holmes-Farley]

Randy- Thank you very much for your continued help. My concern stems from being so far above the suggested range. Without experience / exposure, all we can do is compare to published norms. If we're doing the right thing, we appreciate the confirmation. If not, we're hoping to hear suggested actions.

Again, thank you for your time and counsel.

M

Well, I'm probably the source of that suggested range since BRS is using my recipe. They are just starting doses, not recommended doses:

An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2006-02/rhf/index.php


Dosing Instructions

The dosing instructions are basically the same for each recipe, although any given aquarium will end up using about twice as much of recipe #2 as recipe #1 to add the same amount of calcium and alkalinity.

To initiate dosing, first adjust calcium and alkalinity to roughly their correct ranges. This may require a substantial dose of just the calcium part if calcium is low (e.g., below 380 ppm). I would suggest targeting calcium between 380 and 450 ppm, and alkalinity between 2.5 and 4 meq/L (7-11 dKH; 125-200 ppm calcium carbonate equivalents).

This calculator shows how much of what parts to add in order to boost one or both of the parameters by a certain amount:
Reef chemicals calculator
http://home.comcast.net/~jdieck1/chem_calc3.html

Then, once things seem roughly correct, select a starting daily dose for routine dosing. Here are some suggested starting doses, but the exact values do not matter much. The suggested doses apply to both recipes.

After a few days of dosing, note whether alkalinity is low, high or on target. Only bother to test alkalinity, not calcium, during this period, because it is much more sensitive than calcium to over- or underdosing. Adjust the dose up or down as necessary to increase or decrease the alkalinity.

Once you have determined the proper dose, continue it until there is a substantial reason to adjust it (such as falling alkalinity as the corals increase in size). When adjusting the dose, raise or lower both of the recipe's parts together.

Resist the temptation to keep jiggering calcium and alkalinity independently. They will need occasional corrections, but that should not be the normal course of dosing unless there are substantial outside influences, such as water changes with a salt mix that does not match the tank's parameters or an error in making the mixes.

Check alkalinity fairly frequently to make sure the dosing continues at a suitable rate. Check it maybe once a week to once a month (or less as you get more experienced with the system and the tank). Check calcium once a month to once every few months to make sure it continues on track.

Remember to add an appropriate amount of Part 3 each time you finish adding a gallon of Parts 1 and 2.

 

[Salt1972]

Well, I'm probably the source of that suggested range since BRS is using my recipe. They are just starting doses, not recommended doses:

An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2006-02/rhf/index.php


Dosing Instructions

The dosing instructions are basically the same for each recipe, although any given aquarium will end up using about twice as much of recipe #2 as recipe #1 to add the same amount of calcium and alkalinity.

To initiate dosing, first adjust calcium and alkalinity to roughly their correct ranges. This may require a substantial dose of just the calcium part if calcium is low (e.g., below 380 ppm). I would suggest targeting calcium between 380 and 450 ppm, and alkalinity between 2.5 and 4 meq/L (7-11 dKH; 125-200 ppm calcium carbonate equivalents).

This calculator shows how much of what parts to add in order to boost one or both of the parameters by a certain amount:
Reef chemicals calculator
http://home.comcast.net/~jdieck1/chem_calc3.html

Then, once things seem roughly correct, select a starting daily dose for routine dosing. Here are some suggested starting doses, but the exact values do not matter much. The suggested doses apply to both recipes.

After a few days of dosing, note whether alkalinity is low, high or on target. Only bother to test alkalinity, not calcium, during this period, because it is much more sensitive than calcium to over- or underdosing. Adjust the dose up or down as necessary to increase or decrease the alkalinity.

Once you have determined the proper dose, continue it until there is a substantial reason to adjust it (such as falling alkalinity as the corals increase in size). When adjusting the dose, raise or lower both of the recipe's parts together.

Resist the temptation to keep jiggering calcium and alkalinity independently. They will need occasional corrections, but that should not be the normal course of dosing unless there are substantial outside influences, such as water changes with a salt mix that does not match the tank's parameters or an error in making the mixes.

Check alkalinity fairly frequently to make sure the dosing continues at a suitable rate. Check it maybe once a week to once a month (or less as you get more experienced with the system and the tank). Check calcium once a month to once every few months to make sure it continues on track.

Remember to add an appropriate amount of Part 3 each time you finish adding a gallon of Parts 1 and 2.

Thank you Randy. I'm still dosing alkalinity only. When we started dosing 12/23, we did not have a Ca test and we were told to dose similar amounts of Ca & Alk. When we did get the Hanna Ca test on 12/28, it was 592. My thought was to let Ca deplete while we continued to dose Alkalinity. On 12/31, Ca was 566. When we take tests tomorrow, I anticipate that we'll see Ca ~496, which would equate to approximately 10ppm/day depletion rate. If that holds true, the calculator says that 90mL Ca will make a +10ppm Ca change in our system. That would make sense and mean that when levels stabilize, dosing would require 90mL Alk & 90mL Ca.

Should I continue to add Kalk to our ATO or focus solely on the 2 part?

Tomorrow is 30g water change and full test day. I THINK we're getting the hang of this. Thanks for your help and guidance.

 

[Randy Holmes-Farley]

I'd use limewater in the ATO if it is set up for reasonably slow delivery.

Don't adjust calcium dosing daily.. Look to trends over a few days to a week before making any changes since calcium testing isn't perfect.

I'm surprised calcium would be that high. Do you know how it got that high? What salt mix and have you tested it? The value may be a test error. What kit?

There have been instances of some people reading the syringe backwards. Be sure that more titrant added to get to the color change would mean a higher calcium level.

 

[Salt1972]

Randy -

We added some new acropora frags on January 10 and noticed some lightening in the tips. I learned on R2R that our 10dKH alkalinity target was likely too high for the lower nutrient levels we run. So, I decreased our dosing schedule in an effort to target 8-8.5dKH. In order to maintain 10dKH, we had been dosing 60-70mL daily to maintain a 1.4dKH depletion rate per day.

We have not dosed at all since Sunday and our Alk has stabilized at 8.2dKH for the last 3 days.

So... how could a 1.4dKH per day consumption rate at 10dKH equate to zero depletion at 8.2dKH? I'm confused.

 

[Randy Holmes-Farley]

It will continue to drop, but more slowly(assuming you are not adding alk somehow), but both coral calcification and abiotic precipitation are higher at higher alk and at higher pH (which also likely dropped a bit when you stopped dosing).