How a Two Part Alkalinity and Calcium System Works, and Why it Matters

[excurrent]

Beautiful. Any thoughts on Tropic Marin's All-For-Reef?

 

[Randy Holmes-Farley]

Beautiful. Any thoughts on Tropic Marin's All-For-Reef?

Sure. It, and products like it such as Salifert all in one, have pros and cons relative to two part systems.

The main pro is convenience.

The main cons are a slight pH reducing effect (likely too small to easily see), cost, and complications when trying to use it in a system with automated testing and dosing system.

Like a two part that contains extra trace elements, the amount they add is tied to the calcification rate and thus cannot be adjusted separately in a way that might be more suited to your systems needs.

 

[Discotu]

@Randy Holmes-Farley is there a suitable off the shelf substitute for the TM sodium chloride free salt?

Thanks!

 

[Randy Holmes-Farley]

@Randy Holmes-Farley is there a suitable off the shelf substitute for the TM sodium chloride free salt?

Thanks!

Aquaforest Mineral Salt.

 

[KTTX]

Beautiful. Any thoughts on Tropic Marin's All-For-Reef?

You still have to maintenance dose to get it back in line from time to time.

 

[Cool tangs]

We are talking, for example, about potassium (and every other ions except sodium or chloride).

This is the pertinent section:

Accumulating Sodium and Chloride

A very important consequence of using a two part is that sodium and chloride are added with every dose. Over time, this effect is quite significant. The actual salinity increase will vary based on exactly what other ingredients are incorporated into the two part, and in what form, but we can estimate the minimum effect one would see without water changes from just the alkalinity and calcium additions.

Assumption: add 1 dKH of alkalinity and the balanced amount of 7 ppm calcium each day. 1 dKH of alkalinity causes 0.36 meq/L of sodium to accumulate, or 8 mg/L sodium. The calcium chloride addition will add 12.4 ppm of chloride. Importantly, the Na to Cl ratio is exactly that found in NaCl, and we will come back to that later. We are thus adding 8 + 12.4 mg/l every day, or 632 mg/L in a month = 0.63 ppt each month =7.5 ppt in a year. Note that this is a minimum effect and does not count additions of other ions that may be present, such as sulfate.

This salinity rise means that aquarists may have to offset that rise by removing some salt water periodically and replacing it with fresh. It may happen partly by skimming, but will also likely require some intervention. Do not rely on the above number for intervention purposes because some two parts may contain much more material (e.g., sulfate, etc.). Make the changes as you would for any other factor impacting salinity: by testing and adjusting when needed).

Further, when one lowers the salinity to offset the rise from the accumulating sodium and chloride, one is necessarily depressing every other ion in the water. For example, if you dose at the 1 dKH per day rate, do no water changes, then after a year drop the salinity by 7.5 ppt, the concentration of every ion in the water will drop by a factor of (35-7.5 ppt)/(35 ppt) to 79% of its value on the first of the year. Potassium, for example, would drop from 400 ppm to 316 pm. Even worse, magnesium is not only depressed by this factor (1300 ppm to 1027 ppm) but was also getting consumed along the way.

Also to get through my thick skull..

Is there a negative impact or a balance that needs to happen with the leftover sodium and chloride ratio?

So for example my tank when dosing a balanced chemical like calcium hydroxide. I can keep my tank calcium good with just calcium hydroxide but my alkalinity drops off and can't keep up so I also have to dose a alkalinity buffer (can't think of the chemical I'm dosing right now) to keep the alk up. So my question is also related to 2 part dosing if we where to also dose say more calcium or more alkalinity because a tank was not using these in your standard one to one ratio.

So my question is, can you have a imbalance of the leftover sodium and chloride ratio? Is that a thing? Does it matter? Or does sodium and chloride get seen the same when it contributes to the raising salinity(it's just salinity that's it)? A.K as a general reefer, is this over thinking it. Just test salinity, if it raises. Do a water change, or remove some tank water and replace with RO fresh water to rebalance the salinity and be done with it. Don't think any further. Obviously also checking to make sure parameters are still in check after lowering the salinity, alk, calc, mag, ICP to traces, etc correct as needed after salinity correction.

Thanks in advance. Enjoying learning more, I plan to switch to 2 part with trace as kalk is doing my head in and becoming a chore. New tank build I want to keep it simple . everyone has there own definition of simple. I over complicate things and over think

 

[Randy Holmes-Farley]

Also to get through my thick skull..

Is there a negative impact or a balance that needs to happen with the leftover sodium and chloride ratio?

So for example my tank when dosing a balanced chemical like calcium hydroxide. I can keep my tank calcium good with just calcium hydroxide but my alkalinity drops off and can't keep up so I also have to dose a alkalinity buffer (can't think of the chemical I'm dosing right now) to keep the alk up. So my question is also related to 2 part dosing if we where to also dose say more calcium or more alkalinity because a tank was not using these in your standard one to one ratio.

So my question is, can you have a imbalance of the leftover sodium and chloride ratio? Is that a thing? Does it matter? Or does sodium and chloride get seen the same when it contributes to the raising salinity(it's just salinity that's it)? A.K as a general reefer, is this over thinking it. Just test salinity, if it raises. Do a water change, or remove some tank water and replace with RO fresh water to rebalance the salinity and be done with it. Don't think any further. Obviously also checking to make sure parameters are still in check after lowering the salinity, alk, calc, mag, ICP to traces, etc correct as needed after salinity correction.

Thanks in advance. Enjoying learning more, I plan to switch to 2 part with trace as kalk is doing my head in and becoming a chore. New tank build I want to keep it simple . everyone has there own definition of simple. I over complicate things and over think

Occasional doses to alkalinity only are not going to be a problem and I’d do nothing special.

If one is regularly dosing more or less of one part of a correctly balanced two part (that is, one designed for 1;1 dosing) then when using something like Balling Part C, I’d assume one is using the average of the two.