Cost of Water Changes Vs Dosing in Maintaining Calcium and Alkalinity

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My biggest concerns for most tanks are organics that don’t bind to GAC and the commercial resins folks use, and there is little to no dats on which organics any of these methods bind in a reef tank.

Accumulations of some inorganic ions are also a concern, especially if you do not get quality icp testing, but even if you do, water changes might be the best way to reduce them.

What would be an example of these organics that you are concerned with?
 
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Randy Holmes-Farley

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Toygar Niron

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Hello,

There may be a perception error here. Water change can make up for some missing elements, but this is not its main task. This perspective can be misinterpreted.

Thank you
 
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Randy Holmes-Farley

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Hello,

There may be a perception error here. Water change can make up for some missing elements, but this is not its main task. This perspective can be misinterpreted.

Thank you

The purpose of this thread is only to answer the issue of cost for maintaining alk and calcium. Some folks have explicitly claimed it is cheaper than dosing, which it is not.

It is certainly true that water changes have other reasons to do them, and I recommend them for most people.
 

Toygar Niron

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The purpose of this thread is only to answer the issue of cost for maintaining alk and calcium. Some folks have explicitly claimed it is cheaper than dosing, which it is not.

It is certainly true that water changes have other reasons to do them, and I recommend them for most people.
Hello,

Yes, it's clearer now! So let's look at this from two different angles;

If you have a sps aquarium this means you will consume a lot of kh ca and mg and the loss rate will increase as your corals grow.

However, if you keep soft types, these values rarely drop and they do not consume as much as sps types.

In this case; Adding additives to a Sps-heavy aquarium may be the least expensive method.. However, if soft species predominate, a high value salt and high salinity may also suffice.

So the answer to this question may vary from aquarium to aquarium, as always:)

Thank you
 
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Randy Holmes-Farley

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Hello,

Yes, it's clearer now! So let's look at this from two different angles;

If you have a sps aquarium this means you will consume a lot of kh ca and mg and the loss rate will increase as your corals grow.

However, if you keep soft types, these values rarely drop and they do not consume as much as sps types.

In this case; Adding additives to a Sps-heavy aquarium may be the least expensive method.. However, if soft species predominate, a high value salt and high salinity may also suffice.

So the answer to this question may vary from aquarium to aquarium, as always:)

Thank you

I don’t see how additives will ever be more costly than a water change.

Do you see a scenario where that is the case?
 

Toygar Niron

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Katkı maddelerinin su değişiminden daha pahalıya nasıl mal olacağını anlamıyorum.

Durumun böyle olduğu bir senaryo görüyor musunuz?
Hello,

it's close to impossible. Actually, this is not a topic that should be discussed much. It is clear which elements and in what proportion salt brands contain. At what point they cannot compensate for the losses can also be calculated mathematically. After this point, the contribution is mandatory and there is no other option.

Alternatively, the added elements can be purchased in powder form rather than known brand additives and manually added to the salt. This requires some chemistry knowledge and can cut costs significantly. However, in the chronic salt problem, a homogeneous mixture at low levels is unlikely for the end user. You are the expert on this subject :)

Thank you
 
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Roli's Reef Ranch

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Now add in a 3rd option of dosing KALK and show how expensive dosing 2 part is by comparison! lol
:cool:


...actually I'll do some of the math for ya...

Mrs Wages Pickling lime is about $4 per 16oz bag.
16oz is good for about 96 teaspoons.
$4 divided by 96 teaspoons is approximately $0.04 per tsp.
2tsp per gallon for saturated kalk, so $0.08 per gallon of end-use product.

For the above example on a 100g system and you want to raise your ALK from 7 to 8 you would need 112fl oz of KALK or a grand total cost of $0.07!

For perspective dosing the 2 part from the original example is SIX times more expensive than using KALK, not to mention you are also getting CAL and a pH boost essentially for free since the 2-part example from above is the cost to only dose ALK.
If you REALLY want to get cheap and crazy, try Arm and Hammer Super Washing Soda (sodium carbonate for $4.55/55 oz on Amazon. 2 cents a day per dKh on my 100 gallon tank (i've been running this for a long time and ICPs are good to go. I add TM trace which adds another 7 cents a day. I have it on good authority that a major brand (starting with a B, but doesn't end in an S) actually just repackages this stuff and charges dozens of times more for it after adding a bit of trace.

Screenshot 2022-09-21 9.33.03 PM.png
Screenshot 2022-09-21 9.36.26 PM.png
IMG_3344.jpg
 

Empti

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My biggest concerns for most tanks are organics that don’t bind to GAC and the commercial resins folks use, and there is little to no dats on which organics any of these methods bind in a reef tank.

Accumulations of some inorganic ions are also a concern, especially if you do not get quality icp testing, but even if you do, water changes might be the best way to reduce them.
Do you think doing infrequent but larger % water change would be a good in compromise or would the risks of instability/parameter swings outweigh the benefits of clearing organic/inorganic build up.
 
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Randy Holmes-Farley

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Do you think doing infrequent but larger % water change would be a good in compromise or would the risks of instability/parameter swings outweigh the benefits of clearing organic/inorganic build up.

I think more often and slower and smaller changes are better. I’m not sure what the compromise is.
 

Empti

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I think more often and slower and smaller changes are better. I’m not sure what the compromise is.
Sorry probably wasnt super clear - compromise of saving money. No water changes is obviously the cheapest but with the concern of build up of organics + inorganic ions that you mentioned was thinking that occasional larger % water changes would mitigate build ups while still not spending as much money as regular/smaller water changes.
 
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Randy Holmes-Farley

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Sorry probably wasnt super clear - compromise of saving money. No water changes is obviously the cheapest but with the concern of build up of organics + inorganic ions that you mentioned was thinking that occasional larger % water changes would mitigate build ups while still not spending as much money as regular/smaller water changes.

The total effect of 30 changes of 1% each is the same as one 26% all at once change, so the costs are not too different to reduce contaminants, unless the all at once changes get very large.
 
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