You cant make tank water of pure chloride + RO/DI ? Can you ?Originally Posted by Floyd R Turbo
You cant make tank water of pure chloride + RO/DI ? Can you ?
Specific gravity is the "top of the bucket"...35 g/l (1.025 SG) is a full bucket.
Your total gallons is how big your "bucket" is.
Your ionic balance is the ratio of Sodium:Chloride:Magnesium:Calcium...etc.. in NSW.
Corals use Calcium, Magnesium, Strontium, and other "trace metals", but not Chloride, Sulfate, Sodium, or Borate.
If you replace the used Calcium or Magnesium ions with a bonded Chloride ion (as in BRS 3 part) you will overfill "the bucket" and your SG will go beyond 1.025 because you are adding more "salt" and it is not being consumed.
For every Calcium/Magnesium ion you replace you add one Chloride ion.
In this case, the number of Chloride ions will be out of ratio to NSW. Because you added a whole bunch of Chloride with that Calcium and Magnesium.
The Chloride now takes the place of the Cal/Mag when you test your SG, but your Cal/Mag test low. You are running out of room at 1.025 SG for Cal/Mag. In order to maintain your Cal/Mag your SG has to go beyond 1.025.
If you remove salt from the "bucket" via a RO/DI PWC you remove a percentage of everything. Not just Chloride. This does not correct the skewed ratio. The amount of chloride in the mix is still above what NSW is. Only now you have more room to further skew the ratio before you hit your max SG.
If you could repeat this practice you would eventually end up with a pure chloride solution at 1.025 SG.
This is regarding Chloride only, and not the myriad of other "additives" that help throw things off.
I hope that explains it.
What about when you also add baking soda... doesn't the sodium combine with the extra chloride to add extra salinity?
That is making more sense now, I'm following the logic.
So this is what I do in my system, you tell me if there is an issue here:
I add BRS Alk Soda Ash several times a day (this is Sodium Carbonate) - I add about 2 mL of this per day (tank goes through it FAST) <<<--OOPS I meant 2 Fluid Ounces or 60ml/day
I add BRS Cal (Calcium Chloride) at roughly the same rate, just not every day.
Put those 2 together and I am adding both sodium and chloride, am I not? People use dosing systems and use this stuff all the time in this fashion, if this was an issue I think it would be more widespread.
I keep levels of Alk around 8-9 and Cal around 420, and I rarely have to adjust Mag.
"Salinity Creep" has been mentioned on here but I don't think anyone has raised this issue, in fact I've never heard of this anywhere.
I only used Chloride as my example. But I listed, Sodium, and Sulfate as two other major additions that can throw off ratios.
My assumption as to why this isn't an issue raised around here is:
People are still doing water changes, and even a small PWC compared to the amount being dosed is significantly more. This brings ratios close to NSW again.
The amount of Chloride/Sodium/Sulfate they are dosing is small, due to light load of calcifying stock in their tanks.
They are using Kalkwasser or other methods that do not add extra ions.
They are misdiagnosing their low Cal/Mag/dKH.
I was dosing over 100 ml of BRS Cal a day and could not keep up with demand (doubtful), or my Cal was precipitating out. I don't know, but I added 30 gallons of new salt water (linked a new tank) and a Calcium reactor. Cal/Alk now sit at 420/10 all the time.
Some will bond if they get close enough, but only a small amount. It's the same reason why Calcium reactor effluent doesn't form calcite when it hits the higher pH of the tank water. Even if all of the Chloride bonded to Sodium and you did a fresh water reset to 1.025 the ion ratio count would be off by whatever margin it was off when you did the fresh WC. On account of other ions being precipitated, used, removed with a FWC.What about when you also add baking soda... doesn't the sodium combine with the extra chloride to add extra salinity?
I corrected my above example. What I am currently doing is dosing roughly 2 fluid ounces per day of BRS Alk and Cal.
Looking at this then, I am replenishing the Alk and Cal in a form that then provides both Sodium and Chloride ions in proportion, am I not? Thus the net effect would be an increase in salinity over time, but the sodium and chloride ions would still be in balance. So removing a few gallons from a 100 gallon system and replacing that with RO/DI would essentially dilute everything in the tank by a percentage, and the continued dosing would raise it up again, and the cycle would repeat.
So in that example, over a very long term, I could end up with a solution containing the correct balance of Sodium and Chloride, and the levels of Cal and Alk would be maintained, but pretty much everything else would be out of balance. Then if Mag was occasionally adjusted, this would introduce additional free chloride and skew the ratio.
So what are the other things that would be out of balance in the above scenario, and how would this affect the life in the aquarium?
You mention misdiagnosing cal/alk/mag, are you speaking of misinterpreting tests, or are you saying that an artificially skewed ionic ratio can cause erroneous test readings?
This seems like a very good argument for using Kalkwasser or other methods. It also may be a good argument for the 10% monthly PWC argument. Thank you for your continued explanation of this. This is of great benefit to the scrubber community and I wish to fully understand this. I think the purists find issues like this to scoff at us and I wish to overcome this.
The only problem with with the above is that as your SG increases you push out of solution other ions so that more of the solution is taken up by Sodium/Chloride. If you could continued to does BRS 2 part and reset your SG to 1.025 you would end up with a pure solution of Sodium/Chloride eventually. There wouldn't be any room for the Ca/Alk or other ions. They would precipitate out faster than you could add them. Doing a fresh WC only makes the problem worse, while masking the issue.Looking at this then, I am replenishing the Alk and Cal in a form that then provides both Sodium and Chloride ions in proportion, am I not? Thus the net effect would be an increase in salinity over time, but the sodium and chloride ions would still be in balance. So removing a few gallons from a 100 gallon system and replacing that with RO/DI would essentially dilute everything in the tank by a percentage, and the continued dosing would raise it up again, and the cycle would repeat.
See: Composition of Sea Water by mass . All of the other constituents of the mixture will get squeezed out, and won't be able to be added back in untill the ratio of Chloride/Sodium are reduced.
Good to know. So basically, the answer for long-term success here is:
1) Don't rely on various alk/cal supplements for maintaining appropriate levels of Cal/Alk/Mag unless you are doing so in conjunction with regular PWCs
2) If not relying on regular PWCs, use Kalkwasser or another form of supplementation that does not bind the additive to free chloride/sodium
3) if levels are depleted faster than what can be supplemented with Kalk in top-off water, and BRS or the like is necessary, incorporate PWCs into the regimen.
As to #2, forgive me for a newbie question but I'm still learning many things along the way here, but what are the various methods of maintaining Calcium, Alkalinity, and Magnesium that do not result in a skewed ionic ratio that may be used in conjunction with a minimalist PWC routine?
As to #3, are there products that can be dosed in the same manner (with a dosing pump) that do not skew the ratio? This may be the same as the question above I guess...
Wow i had to read it six times but this acually makes sence.. i wonder what can i do if kalk and waterchanges then cant keep up?
You got it. Small adjustments here and there won't be much different than using different brands of salt mix, or even different batches of the same brand as far as ion ratios are concerned.
Only Calcium Hydroxide (Kalkwasser), or dissolved Calcium Carbonate (Calcium reactor, or Kents "Liquid Calcium Reactor"). The cost of a decent dosing pump is about equal to a DIY Calcium reactor, and is by far the best cost over time ratio. If you are set on using a doser, the Kents Liquid Calcium Reactor can be found cheaply, but is pricey in my opinion. Kalkwasser is great, if you love constant adjustments and tinkering.2) If not relying on regular PWCs, use Kalkwasser or another form of supplementation that does not bind the additive to free chloride/sodium
3) if levels are depleted faster than what can be supplemented with Kalk in top-off water, and BRS or the like is necessary, incorporate PWCs into the regimen.
As to #2, forgive me for a newbie question but I'm still learning many things along the way here, but what are the various methods of maintaining Calcium, Alkalinity, and Magnesium that do not result in a skewed ionic ratio that may be used in conjunction with a minimalist PWC routine?
As to #3, are there products that can be dosed in the same manner (with a dosing pump) that do not skew the ratio? This may be the same as the question above I guess...
There are some more difficult to acquire calcium additives, but there not worth the effort; search Advanced Aquariest.
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