Brs 2 part equal dosing?

[Randy Holmes-Farley]

I tested my tank water and had the lfs test it and the results confirmed all my testing was consistent with theirs. I didn't have them test my mix water. The salinity was 35ppt which I checked with a calibrated refractometer. My tank measures this and my made up water. Lfs also confirmed this with the tank water i brought in. I mix approximately 30 gallons using rodi di water and tropic marin classic.
My testing consistently shows my mag level dropping then I dose an appropriate amount to bring it up to 1350-1400 which it does. It will stay there for awhile before dropping again. My magnesium is going somewhere. Attached are testing results

If the salt mix is actually lower than your target, then of course that will create additional demand when you use it for water changes. If it claims 1300 and you want 1450, then one suggestion is to just always add magnesium into the salt mix. I did that for years with IO which used to be low. I never measured it, just added 150 ppm of magnesium to it.

Overall, I still think you'd be better off not measuring and just adding the recommended amount based on the recipe. But if you really believe your magnesium testing is consistently accurate, then there's no reason to not do that, or at least use the testing to confirm that the recipe plan is working.

 

[drtechno]

Along the topic of this post, how is it possible that I am dosing 170cc/day of BRS sodium bicarbonate and only 20cc/day of BRS calcium in order to maintain an Alk of 9dkh and calcium 480-500. My calcium is that high so I keep cranking down on the calcium dosing - but that is so far out of balance. Mag is 1450-1500. I can’t dose balanced because that would mean cranking my calcium up 100+cc/day which I assume would send it thru the roof.

This is in a very lightly stocked 240 gal system (200 DT 40 sump) with a 2 gal/day AWC of tropic Marin pro reef salt. Ph 8-8.2

I have no clue why my dosing needs to be so unbalanced.
Ideas?

 

[gbroadbridge]

Along the topic of this post, how is it possible that I am dosing 170cc/day of BRS sodium bicarbonate and only 20cc/day of BRS calcium in order to maintain an Alk of 9dkh and calcium 480-500. My calcium is that high so I keep cranking down on the calcium dosing - but that is so far out of balance. Mag is 1450-1500. I can’t dose balanced because that would mean cranking my calcium up 100+cc/day which I assume would send it thru the roof.

This is in a very lightly stocked 240 gal system (200 DT 40 sump) with a 2 gal/day AWC of tropic Marin pro reef salt. Ph 8-8.2

I have no clue why my dosing needs to be so unbalanced.
Ideas?

Have you actually tried dosing equally and seeing what happens over a month or two?

I'm quite sure that you will find that Calcium will not climb excessively unless the solutions have not been mixed at the correct ratio.

BTW Calcium at 500ppm is not excessively high.

 

[ariellemermaid]

If the salt mix is actually lower than your target, then of course that will create additional demand when you use it for water changes. If it claims 1300 and you want 1450, then one suggestion is to just always add magnesium into the salt mix. I did that for years with IO which used to be low. I never measured it, just added 150 ppm of magnesium to it.

Overall, I still think you'd be better off not measuring and just adding the recommended amount based on the recipe. But if you really believe your magnesium testing is consistently accurate, then there's no reason to not do that, or at least use the testing to confirm that the recipe plan is working.

If you don’t mind, I just have a few questions on this topic after reading your paper. I love the idea of cheaper alternatives to BRS repackaged ice melt, and that’s the “cheap” option.

Am I reading correctly that your recipe calls for adding the same amount of Mg (2 1/2 cups) all at once after a gallon of 2 part regardless of whether the tank is 5 gallons or 500 gallons? It’s just such a wide PPM swing between the two tanks in both directions (because the small tank would take a lot longer to use a gallon and therefore have low numbers for a much longer period).

You also mention there will be a significant increase in salinity (29%). I assume this should be mitigated with hyposaline water changes?

Regarding water changes, there’s a movement within the community for getting to no water changes. It sounds like you would completely disagree because of the sulfate data? Not only that, we really need to be doing 30% changes a month? That’s a lot more salt than a lot of folks are currently buying and it’s one of the biggest ongoing expenses . I’m guessing there’s no way to get the needed ions without the extra sulfate?

Regarding testing, are you suggesting that all Mg testing is neither precise nor accurate? Like after gallons and gallons of BRS 2 part I’ve never added a Mg solution because I’m at least getting stable Trident numbers (with water changes). In other words, the numbers at least seem precise and repeatable even if not accurate (and match other test kits). I assume you would have no qualm with mass spec results?

Finally, related, you seem opposed to testing in general. You said to check calcium once a month to few months, Alk once a week to once a month (or less), Mg never. The mantra oft repeated is that the numbers don’t matter that much, it’s all about stability. Doesn’t rare testing and adjustment inherently lead to less tank stability than say Trident controlled dosing as the tank grows and changes and gets 30% frequent water changes? With the caveat that the similar ratios are kept so the math works out.

Just in the past month or two my tank is dosing 10ml less per day to keep the numbers stable. Without that, my numbers would have drifted up, and I also wouldn’t know how much to adjust dosing by. I’d just be guessing or doing napkin math, and stability would further drift until I experimentally figure it out.

Thanks!

 

[drtechno]

Have you actually tried dosing equally and seeing what happens over a month or two?

I'm quite sure that you will find that Calcium will not climb excessively unless the solutions have not been mixed at the correct ratio.

BTW Calcium at 500ppm is not excessively high.

Let me give it a try

Edit. I’m also dosing 1000cc of kalkwasser daily but that’s balanced so should alter the discussion.

I guess the flip side is why would I do this? My Ca is fine (to high) so why dose even more Ca just to say it’s balanced dosing? Is there any point to it other than in name alone?

@Randy Holmes-Farley Is there anything beneficial to adding even more Ca in the name of balanced dosing despite levels being fine already?

 

[Randy Holmes-Farley]

Is there anything beneficial to adding even more Ca despite it being fine?

The answer to that depends on what exactly you are dosing, but if your goal is to lower calcium then it is ok to keep dosing alk and little or no calcium.

Just bear in mind that this is not the result of ongoing unbalanced consumption to the degree you note (unless you use a sulfur denitrator which chews through alk).

You are adding about 1 dKH per day, and only about 1 ppm of calcium per day. That degree of imbalance could come from trying to fight against substantial water changes that do not match the tank, or from calcium test error.

 

[Randy Holmes-Farley]

If you don’t mind, I just have a few questions on this topic after reading your paper. I love the idea of cheaper alternatives to BRS repackaged ice melt, and that’s the “cheap” option.

Am I reading correctly that your recipe calls for adding the same amount of Mg (2 1/2 cups) all at once after a gallon of 2 part regardless of whether the tank is 5 gallons or 500 gallons? It’s just such a wide PPM swing between the two tanks in both directions (because the small tank would take a lot longer to use a gallon and therefore have low numbers for a much longer period).

You also mention there will be a significant increase in salinity (29%). I assume this should be mitigated with hyposaline water changes?

Regarding water changes, there’s a movement within the community for getting to no water changes. It sounds like you would completely disagree because of the sulfate data? Not only that, we really need to be doing 30% changes a month? That’s a lot more salt than a lot of folks are currently buying and it’s one of the biggest ongoing expenses . I’m guessing there’s no way to get the needed ions without the extra sulfate?

Regarding testing, are you suggesting that all Mg testing is neither precise nor accurate? Like after gallons and gallons of BRS 2 part I’ve never added a Mg solution because I’m at least getting stable Trident numbers (with water changes). In other words, the numbers at least seem precise and repeatable even if not accurate (and match other test kits). I assume you would have no qualm with mass spec results?

Finally, related, you seem opposed to testing in general. You said to check calcium once a month to few months, Alk once a week to once a month (or less), Mg never. The mantra oft repeated is that the numbers don’t matter that much, it’s all about stability. Doesn’t rare testing and adjustment inherently lead to less tank stability than say Trident controlled dosing as the tank grows and changes and gets 30% frequent water changes? With the caveat that the similar ratios are kept so the math works out.

Just in the past month or two my tank is dosing 10ml less per day to keep the numbers stable. Without that, my numbers would have drifted up, and I also wouldn’t know how much to adjust dosing by. I’d just be guessing or doing napkin math, and stability would further drift until I experimentally figure it out.

Thanks!

There’s no reason to not spread out the magnesium dosing, especially in small tanks. Dose it at 16% of the calcium dose.

The salinity rise, if not offset by things like skimming, then just remove some tank water once in a while and replace with ro/di.

I do not understand the question about sulfate and water changes. My recipe is sulfate balanced. My current preferred recipe uses Balling Part C or AF mineral salt in place of my third part, and when doing so there is no need for water changes due to the use of this recipe.

In testing, I’m only opposed to magnesium testing as it is often more problem than it is worth. When setting up a dosing method you may need to measure alk a lot to get things straight. Then you can reduce the testing. What I am against is constantly jiggering dosing to match tests that have inherent variability. Look to longer trends when making dosing changes.

 

[Randy Holmes-Farley]

FWIW, I discuss all of the significant ways that can contribute to alk and calcium demand imbalances here:

When Do Calcium and Alkalinity Demand Not Exactly Balance? by Randy Holmes-Farley

 

[drtechno]

Thanks Randy.
It doesn’t appear to be a test error as two separate test kits are both reading similarly high calcium. Also the water changes are with TM pro reef which is something like 8.5 dkh and 450ca so I don’t think I’m fighting water changes either (1% per day).
I don’t running anything extraneous on the tank like sulfur or carbon.

Just the typical skimmer/rollermat/uv setup. Dosing kalk and BRS 2 part (sodium bicarbonate) and tropic Marin c balling method. Neonitrate at 20cc/day but this imbalanced addition has been going on way before that. That’s it.

I don’t see any precip or other issues.

Out of curiosity, since I’ll start dosing Ca to see what happens, is there a level of calcium beyond which I would want to stop dosing it? 600? I have no clue on that

We also live like one town from you as well so maybe I should just have you over for a beer instead LOL

Edit- checking out the article. Alk demand is low in the tank so I see that this could exacerbate the effects

 

[Randy Holmes-Farley]

Wait, sodium bicarbonate? Or carbonate?

 

[Randy Holmes-Farley]

The nitrate dosing adds alk, assuming neonitro is actually nitrate.

 

[drtechno]

Wait, sodium bicarbonate? Or carbonate?

I’m doing my 2 part with BRS calcium chloride and sodium BIcarbonate. I was staying away from soda ash in my 2 part because at one point I had problems with too high of a pH (9+).

Awesome article about the reasons for imbalanced uptake. So if I am understanding correctly, if those are the case, then there WOULD be situations where you dose unequal amounts of Ca and Alk. But still mine seems to be an extreme

 

[Randy Holmes-Farley]

I’m doing my 2 part with BRS calcium chloride and sodium BIcarbonate. I was staying away from soda ash in my 2 part because at one point I had problems with too high of a pH (9+).

Awesome article about the reasons for imbalanced uptake. So if I am understanding correctly, if those are the case, then there WOULD be situations where you dose unequal amounts of Ca and Alk. But still mine seems to be an extreme

The reason I asked about bicarbonate is that it’s recipe is half as potent, and sometimes folks use the full strength calcium part, which would not be designed for 1:1.

How did you make the calcium part?0

 

[drtechno]

The reason I asked about bicarbonate is that it’s recipe is half as potent, and sometimes folks use the full strength calcium part, which would not be designed for 1:1.

How did you make the calcium part?0

Interesting!

I didn’t know that. So I use what’s printed on the back of the BRS bags-
CaCl. 2.5 cups per gal
sodium bicarb. 1 cup 2 tablespoon per gal

So those recipes on the back aren’t designed for balanced dosing?

 

[ariellemermaid]

There’s no reason to not spread out the magnesium dosing, especially in small tanks. Dose it at 16% of the calcium dose.

The salinity rise, if not offset by things like skimming, then just remove some tank water once in a while and replace with ro/di.

I do not understand the question about sulfate and water changes. My recipe is sulfate balanced. My current preferred recipe uses Balling Part C or AF mineral salt in place of my third part, and when doing so there is no need for water changes due to the use of this recipe.

In testing, I’m only opposed to magnesium testing as it is often more problem than it is worth. When setting up a dosing method you may need to measure alk a lot to get things straight. Then you can reduce the testing. What I am against is constantly jiggering dosing to match tests that have inherent variability. Look to longer trends when making dosing changes.

I was referring to this link you posted earlier:

https://reefkeeping.com/issues/2006-02/rhf/index.php

I guess I misunderstood the last part on water changes. It says the rise in sulfate shown in Table 2 (recipe 1, 3a) can be mitigated by water changes. I wasn’t sure what that meant.

Anyway doesn’t matter, that all sounds great to me. Do you have a link for the part 3 with Balling C or Aquaforest mineral salt included? I assume recipe 1 is otherwise the same.

 

[Randy Holmes-Farley]

Interesting!

I didn’t know that. So I use what’s printed on the back of the BRS bags-
CaCl. 2.5 cups per gal
sodium bicarb. 1 cup 2 tablespoon per gal

So those recipes on the back aren’t designed for balanced dosing?

Correct, this is a mish mash of my recipe 1 calcium part and recipe 2 alk part:

An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com

 

[Randy Holmes-Farley]

I was referring to this link you posted earlier:

https://reefkeeping.com/issues/2006-02/rhf/index.php

I guess I misunderstood the last part on water changes. It says the rise in sulfate shown in Table 2 (recipe 1, 3a) can be mitigated by water changes. I wasn’t sure what that meant.

Anyway doesn’t matter, that all sounds great to me. Do you have a link for the part 3 with Balling C or Aquaforest mineral salt included? I assume recipe 1 is otherwise the same.

It means that water changes can also help reduce accumulation of sulfate if you just use Epsom salt for magnesium.