Why do we do water changes so religiously if we can remove the nitrates?

[Greg Gdowski]

Why are we talking about KH then?


Not really, you should be servicing your equipment and discover that seal no matter what a test tells you but if you keep up with your water changes than that rust will never be a problem anyways which is the same thing as testing and then seeking a solution. It just has fewer steps.


Bad salt batches do happen but its pretty vanishingly rare. Odds are you'll discover it pretty fast too and your problems will be bigger than a slight imbalance in trace elements. you hope your consumption remains constant, I hope my salt manufacturer is reliable. as you say, who knows which is better. I'm guessing you don't test your mixed dosing solution to confirm the concentration, nor do you test for contaminants. I would posit that is more or less the same as not testing your newly mixed salt water. some manufacturers ICP test each individual batch of salt and post their results (well at least one)


As you say most people consume Ca ALK and Mg at levels which require dosing. using water changes as your sole source in a tank with calcifying animals is irresponsible these days and not really part of most people's thoughts when they think about doing water changes vs not doing water changes.

We are talking about KH/Alkalinity because it is the easiest parameter of the three (KH, Ca, and Mg) to measure when looking for changes over 1-2 days. All three change more or less with the same proportions -- but the change in KH is the easiest to measure.

It is not a question of bad salt mix. It is a question of whether it is uniformly mixed. If I showed you the quantities of chemicals I put in 5L you would see how problematic that really is for trace chemicals. I am mixing in trace chemicals that are suspended in solution by the distributor. I put 25ml in a 5L volume. I can only imagine what the mass of those trace elements would be in a dry state.

If you are following the normal guidelines of 20%/wk or even 40%/wk you are not solving your rust problem.

In any case, do what you want to do. If it works, that is all that matters.
Some day, do me a favor, take one week where you measure ALK in the morning at 8am and again at 6pm and see how your parameters are changing daily across a week. Don't do any water changes until the end of the week. Its a pain in the butt, but it is worth it. Trust me on this one.

 

[Greg Gdowski]

We are talking about KH/Alkalinity because it is the easiest parameter of the three (KH, Ca, and Mg) to measure when looking for changes over 1-2 days. All three change more or less with the same proportions -- but the change in KH is the easiest to measure.

It is not a question of bad salt mix. It is a question of whether it is uniformly mixed. If I showed you the quantities of chemicals I put in 5L you would see how problematic that really is for trace chemicals. I am mixing in trace chemicals that are suspended in solution by the distributor. I put 25ml in a 5L volume. I can only imagine what the mass of those trace elements would be in a dry state.

If you are following the normal guidelines of 20%/wk or even 40%/wk you are not solving your rust problem.

In any case, do what you want to do. If it works, that is all that matters.
Some day, do me a favor, take one week where you measure ALK in the morning at 8am and again at 6pm and see how your parameters are changing daily across a week. Don't do any water changes until the end of the week. Its a pain in the butt, but it is worth it. Trust me on this one.

Interesting, I don't think I typed the word butt.

 

[Fakegolfnews]

I dont dose or have a skimmer. So water changes keep a consistent supply of trace elements and keep my nutrients stable. Works pretty well, and i never test either haha. Waste of time and money with the lps, softies and aquacultured sps i keep.

 

[Sm51498]

Some day, do me a favor, take one week where you measure ALK in the morning at 8am and again at 6pm and see how your parameters are changing daily across a week

Who says I haven't? I'm not talking about the big three elements, I don't know why you insist on persisting about them. I have agreed you can't practically maintain those with water changes in most reef systems. *Again* They aren't why people do water changes in a reef system typically.

 

[92Miata]

Who says I haven't? I'm not talking about the big three elements, I don't know why you insist on persisting about them. I have agreed you can't practically maintain those with water changes in most reef systems. *Again* They aren't why people do water changes in a reef system typically.

He keeps talking about the big 3 because traces behave *exactly* the same way.

And the big 3 are easy to measure, so they're easy to use for examples.

Trace elements don't get to violate the laws of physics. Dilutions work exactly the same way as with majors.

 

[Greg Gdowski]

Who says I haven't? I'm not talking about the big three elements, I don't know why you insist on persisting about them. I have agreed you can't practically maintain those with water changes in most reef systems. *Again* They aren't why people do water changes in a reef system typically.

I'm saying look at those three because if a reefer doesn't get those right -- trace elements don't matter. They are one of the primary reasons why people are encouraged to change water. The second is to remove unwanted detritus from your tank. Correcting trace elements would not be on my list, IMO as a motivator without evidence from the big 3 (maybe that is where we differ). Here is my reason, if you are not consuming the big 3 -- you are not likely consuming the little tiny elements either. If you are dosing the big 3, it is highly likely you are also dosing the tiny trace elements. Am I dosing the right amount of trace elements? IMO it is no different than believing the manufacturer has the right amount in their salt.

 

[Spare time]

Please quit with trace element nonsense.

There is no standard in regards to what trace elements encompass and salt mix makers don't have a standard anyway. So, when you claim "I water change to replenish trace elements" all you are proving is the amazon driver knows where to deliver the package marked 1d10t.

If you do water changes and have good results then keep doing it but please stop with unproven nonsense. Many of us rarely do water changes and have great results.

Water changes do not 'reset' water conditions to 'perfect' or 'default'. Thats the myth perpetuated by the industry so you keep buying bags of over priced sodium chloride.

Evidence that salt batches are not consistent and won't reset levels? I am not asking for experience but actual evidence.

Also I would be more cautious on saying "many" do not do water changes and don't have a problem. I've dealt with thousands of people in this hobby and I would hesitate saying that many people go without water changes and have no problem. I am not saying it can't be done, just that it is not common.

 

[Greg Gdowski]

Evidence that salt batches are not consistent and won't reset levels? I am not asking for experience but actual evidence.

Also I would be more cautious on saying "many" do not do water changes and don't have a problem. I've dealt with thousands of people in this hobby and I would hesitate saying that many people go without water changes and have no problem. I am not saying it can't be done, just that it is not common.

I would totally agree with this sentiment -- at least within my neck of the woods. It is hard to say how many people dose vs change water. My networking at reef events suggests that the far majority still do water changes. I will also admit that when I decided to try dosing and abandon high volume (re tank size) regular water changes, I did so with much trepidation. A lot of different things can go wrong. Comparatively, far less can go wrong with changing water. Now that I have been doing it for 3years (almost to the day), I can readily say it is really not as bad as I thought it would be. Are we ready for the entire community to embrace it, absolutely not. What I did learn in this process was the value of testing. I'll stop here on this topic.

re salt. There are some historical examples of this. But I wasn't really trying to say there was bad salt out there. I was just trying to say that I was amazed that they could put trace elements in the mix and be confident that every mixed batch was exactly the same. Do I have evidence --- No! However, when you look at the constituent elements and their relative masses -- the trace elements are a remarkable minority. Again, no evidence, just an observation in the process of mixing chemicals for my tank over the last 3yrs.

 

[2Wheelsonly]

Oh look. Another water change thread. Can we please get a sticky about this topic and delete the five new threads a day about water changes. It'll save on server space.

It's 2020, you don't worry about things like server space anymore. We have all moved on past dialup and floppy disks my man and or woman. I'm sure you were being sarcastic so i'm just having fun with it.

 

[2Wheelsonly]

Wow another water change thread going right into the toilet.
Wish we could have one that stays on target with everyone involved.
Have not seen one yet.
Maybe next time, lol.
Im out.

Moral of the story:

Don't do water changes. (and make sure to know your tank thickness before blindly buying an mp10)

 

[Sm51498]

He keeps talking about the big 3 because traces behave *exactly* the same way.

And the big 3 are easy to measure, so they're easy to use for examples.

Trace elements don't get to violate the laws of physics. Dilutions work exactly the same way as with majors.

I'm not sure you understand how consistent water changes actually work to dilute accumulation and remediate depletion. Probably because you've never bothered to model it. Let's walk through it. There are four broad scenarios.

Scenario 1 Depletion faster than remediation:
This is the category the big three fit into but for the purposes of easy math let's call it element x that exists at 100 units per volume in your tank. It uses 25 U/V per week and you do a 20% water change with perfect makeup water every week.
Each number represents concentrations after each week: 80, 64,51,41,33

Scenario 2 Depletion slower than remediation:
*this* is the category for most trace elements. again element x at 100 u/v. this time 10 U/v per week depletion still 20% water changes.
92, 85.6, 80.5, 76.4, 73.1, 70.5..... basically its asymptotically approaches an equilibrium concentration that for most trace elements is sufficient such that it won't limit coral growth. *this* is why talking about alk is nonsensical when you're referring to elements which are used so much slower. Get it?

Scenario 3 Accumulation slower than remediation
the same as scenario two but the curve is inverted. This is why you can dose reasonable, small amounts of trace elements without measuring if you do consistent waterchanges because at worst you'll hit a reasonable equilibrium point.

Scenario 4 Accumulation faster than remediation
Just runaway accumulation, we all know what this looks like.

 

[Afrashz]

Wow....this thread is a lot. It appears at some point it got back on track, then off again, then on again.

Guys why on earth are people arguing on R2R. We are all in this hobby because we love it, why bring negativity into it? We are such a small minority of people (reef keepers) why people are trying to divide us is beyond me. Please guys, with 2020 winding down and a new year right around the corner, let’s just get along and enjoy each others company!! Just remember when you were a new R2R member....negativity like this would’ve turned you away before you joined. Let’s grow the community not break it down...

 

[Greg Gdowski]

I'm not sure you understand how consistent water changes actually work to dilute accumulation and remediate depletion. Probably because you've never bothered to model it. Let's walk through it. There are four broad scenarios.

Scenario 1 Depletion faster than remediation:
This is the category the big three fit into but for the purposes of easy math let's call it element x that exists at 100 units per volume in your tank. It uses 25 U/V per week and you do a 20% water change with perfect makeup water every week.
Each number represents concentrations after each week: 80, 64,51,41,33

Scenario 2 Depletion slower than remediation:
*this* is the category for most trace elements. again element x at 100 u/v. this time 10 U/v per week depletion still 20% water changes.
92, 85.6, 80.5, 76.4, 73.1, 70.5..... basically its asymptotically approaches an equilibrium concentration that for most trace elements is sufficient such that it won't limit coral growth. *this* is why talking about alk is nonsensical when you're referring to elements which are used so much slower. Get it?

Scenario 3 Accumulation slower than remediation
the same as scenario two but the curve is inverted.

Scenario 4 Accumulation faster than remediation
Just runaway accumulation, we all know what this looks like.

I actually wrote an article on this on R2R. I showed graphs of each of the models.
Here is why I talk about Alk.

The balling method puts the trace elements into the main 3 solutions. The assumption is that they (the 3 major elements and the trace elements) are consumed at equal rates. Maybe that is a bad assumption. That is what is done. You don't dose the 3 solutions at different rates. More specifically you don't dose the trace elements independently at their own rates. Again, that is just the way it is done. I don't do repeated ICP tests, but when I have done them after having a stable tank for a long time -- I didn't see runaway parameters with the trace elements.

Here is my other point. Trace elements are measured in parts per billion. There is a great article on trace elements here that compares different reef salts: https://reefs.com/magazine/a-chemic...-in-synthetic-sea-salts-and-natural-seawater/

Here is one conclusion of that study: "It is clear that most synthetic sea salts do not add substantial amounts of trace levels to aquaria when compared to the natural seawater available to the majority of hobbyists."

Here is another: "It must be realized that the data herein are only for one sample of each product at one time and subsequent analysis may produce different values."

Here is another: "The chemical analysis of trace elements is not a straightforward task. A trace element at a concentration of 1 µg/kg (1 ppb) in seawater is in a matrix of elements and compounds that total nearly 35,000,000 µg (Pilson 1998)."

 

[92Miata]

I'm not sure you understand how consistent water changes actually work to dilute accumulation and remediate depletion. Probably because you've never bothered to model it. Let's walk through it. There are four broad scenarios.

I understand how dilutions work just fine.

You should take a minute, read people's posts, and stop assuming everyone on here is an idiot.

The issue isn't how dilutions work - the issue is all the other assertions you're making and not providing evidence for.

 

[MnFish1]

I actually wrote an article on this on R2R. I showed graphs of each of the models.
Here is why I talk about Alk.

The balling method puts the trace elements into the main 3 solutions. The assumption is that they (the 3 major elements and the trace elements) are consumed at equal rates. Maybe that is a bad assumption. That is what is done. You don't dose the 3 solutions at different rates. More specifically you don't dose the trace elements independently at their own rates. Again, that is just the way it is done. I don't do repeated ICP tests, but when I have done them after having a stable tank for a long time -- I didn't see runaway parameters with the trace elements.

Here is my other point. Trace elements are measured in parts per billion. There is a great article on trace elements here that compares different reef salts: https://reefs.com/magazine/a-chemic...-in-synthetic-sea-salts-and-natural-seawater/

Here is one conclusion of that study: "It is clear that most synthetic sea salts do not add substantial amounts of trace levels to aquaria when compared to the natural seawater available to the majority of hobbyists."

Here is another: "It must be realized that the data herein are only for one sample of each product at one time and subsequent analysis may produce different values."

Here is another: "The chemical analysis of trace elements is not a straightforward task. A trace element at a concentration of 1 µg/kg (1 ppb) in seawater is in a matrix of elements and compounds that total nearly 35,000,000 µg (Pilson 1998)."

This is what doesnt make complete sense to me - I get the adding of the 3 solutions - at equal rates - should keep a 'balance' of sorts. What I dont understand is - lets say tank A is being fed with frozen foods - with high levels of 'x' - and tank B is being fed with pellets with minimal or no 'x'. Lets say in another set - tank A has an overabundance of algae 'x' - tank B has no algae of type 'x' but a lot of type 'y' - and they both use different amounts of trace elements (but shoudl use the same amount of alkalinity and Ca. There are lots of examples.

If you don't do very frequent ICP tests (which you say you don't do (I think)) - how do you avoid problems with trace elements - depending on your tank?

 

[Greg Gdowski]

This is what doesnt make complete sense to me - I get the adding of the 3 solutions - at equal rates - should keep a 'balance' of sorts. What I dont understand is - lets say tank A is being fed with frozen foods - with high levels of 'x' - and tank B is being fed with pellets with minimal or no 'x'. Lets say in another set - tank A has an overabundance of algae 'x' - tank B has no algae of type 'x' but a lot of type 'y' - and they both use different amounts of trace elements (but shoudl use the same amount of alkalinity and Ca. There are lots of examples.

If you don't do very frequent ICP tests (which you say you don't do (I think)) - how do you avoid problems with trace elements - depending on your tank?

Honestly, a good question. In retrospect, I guess I use more of a KISS approach. I do ICP tests when I see major problems. I also do water changes when I see those problems. I wish I could say that I could attribute those problems to trace elements -- but in my particular tank I haven't seen them - yet. Who knows, that could change. I try to keep myself informed about the latest changes in how the balling method should be executed -- but in all honesty I just follow the recipe. I don't think it is perfect. My tank has had stumbling points along its 3yr history -- just like everyone else's.

Ironically, my tank is a blend of A and B without the algae issue. I have a harder time keeping nitrates and phosphates at sufficient levels.

I know I am being perceived as a negative trace element person. Of all the chemicals I buy, those are the most expensive. They know that -- and they won't sell them in bulk. I guess I must believe they are essential because I keep buying them. But I see the relative ratios in mixing the solutions and have to wonder just how important they really are and how accurately they are being put into the tank. I mix the solutions a lot -- but that is no different than someone mixing salt solutions and hoping the trace concentrations are consistent and correct from batch to batch. It is the same problem for both techniques. Sorry if I seem to have ruffled feathers yet again.

 

[MnFish1]

Here is my other point. Trace elements are measured in parts per billion. There is a great article on trace elements here that compares different reef salts: https://reefs.com/magazine/a-chemic...-in-synthetic-sea-salts-and-natural-seawater/

Here is one conclusion of that study: "It is clear that most synthetic sea salts do not add substantial amounts of trace levels to aquaria when compared to the natural seawater available to the majority of hobbyists."

Here is another: "It must be realized that the data herein are only for one sample of each product at one time and subsequent analysis may produce different values."

Thought I'd give you my 2 cents - not to argue but because its an interesting discussion. Thanks for that study - it was hard to read - but -- which they do a good job summarizing the difficulties of this study - like you did above) - But those are BIG problems - so its hard to make any conclusion (which they also said) - right?

Here are the conclusions that I read at the end of the article:

• most synthetic sea salts do not have high levels of many trace elements,
• natural seawater is not automatically a safe alternative to synthetic sea salts when it comes to comparing amounts of trace elements in the two solutions,
• past comparisons of synthetic sea salts to natural seawater are flawed because they compared synthetic sea salts to a hypothetical natural seawater that is not available to the majority of marine hobbyists, and
• synthetic sea salts are quite acceptable for long-term use in marine aquaria when considered from the viewpoint of not adding detrimental concentrations of trace elements to the system.

To me - these suggest - that you're correct - doing water changes does not supply trace elements to a great degree (in THESE salts) - there are others - that claim to have trace elements identical to seawater (at least the ones that they feel important - Brightwell neomarine for example). Second - To me the problem with a no-water change system is not low trace elements - its build up of trace elements - or am I totally off base.

 

[jda]

Do I really need to be changing my water weekly? Especially if my nitrate levels are being kept so low between the low bioload, quality protein skimmer, and chaeto.

So much stupidity between the first post and here, but I will offer some actual help for a Fish Only. First, water changes are cheap and effective so if you even consider buying some supplement or magical potion, then just buy some salt - I can change 44g of reef quality water (more like 50g of fish only water) for less than $10. Second, if you want that chaeto to keep growing, you are going to at least need iron and a few other things... which is another reason to change some water instead of buying iron supplement and iron test kit, along with some other supplements and test kits. Research macro algae needs and do the math. That chaeto will be more reef-like than you know right now. The only reason not to change water is if you are just lazy or want to see if you are cool enough to get by without it. You can do quite well without changing water, but even the no-water-change methodologies such as DSR work even harder not to change water and laziness does not work and even they will admit that salt mix and water changes might be cheaper and easier, but they like what they do for other reasons.

 

[Greg Gdowski]

Thought I'd give you my 2 cents - not to argue but because its an interesting discussion. Thanks for that study - it was hard to read - but -- which they do a good job summarizing the difficulties of this study - like you did above) - But those are BIG problems - so its hard to make any conclusion (which they also said) - right?

Here are the conclusions that I read at the end of the article:

• most synthetic sea salts do not have high levels of many trace elements,
• natural seawater is not automatically a safe alternative to synthetic sea salts when it comes to comparing amounts of trace elements in the two solutions,
• past comparisons of synthetic sea salts to natural seawater are flawed because they compared synthetic sea salts to a hypothetical natural seawater that is not available to the majority of marine hobbyists, and
• synthetic sea salts are quite acceptable for long-term use in marine aquaria when considered from the viewpoint of not adding detrimental concentrations of trace elements to the system.

To me - these suggest - that you're correct - doing water changes does not supply trace elements to a great degree (in THESE salts) - there are others - that claim to have trace elements identical to seawater (at least the ones that they feel important - Brightwell neomarine for example). Second - To me the problem with a no-water change system is not low trace elements - its build up of trace elements - or am I totally off base.

Maybe I'm due for another ICP test? I think the risks are inverted for the two techniques. With water changes you risk depletion. With dosing, the worse evil is having buildup and runaway. I guess the good news is that if you are dosing close to the consumption rate the runaway problem typically happens slowly (in either direction).

Do they run away at different rates? That is the 100k question. Lets hope so, I would rather dose less trace elements than more. ;-).

 

[Sm51498]

I understand how dilutions work just fine.

You should take a minute, read people's posts, and stop assuming everyone on here is an idiot.

The issue isn't how dilutions work - the issue is all the other assertions you're making and not providing evidence for.

If you understand it why would you assert that two scenarios with very different outcomes " behave *exactly* the same way "?

Which assertions are those specifically?

The balling method puts the trace elements into the main 3 solutions. The assumption is that they (the 3 major elements and the trace elements) are consumed at equal rates. Maybe that is a bad assumption

I think that it is a wrong assumption since trace consumption could vary wildly depending on the organisms we have in our tanks (for example we know sponges consume more silicates) but that doesn't mean it's not a useful assumption. Rules of thumb are often the best way to control complex systems even when they are based on incorrect models. obviously it works well enough but that leads to the obvious question, How do you not get depleted elements or runaway accumulation if, as we know, those consumption rates vary by organism? Does consumption vary with concentration? Do the trace elements fall out of solution somewhere? are we being sold what we're told? or has TM figured all this out and has built in some kind of safety margin which at normal dosing amounts guarantees your levels won't go too far wrong. I admit, I use this method of dosing. I dose home brewed all-for-reef which does much the same thing. Though I also change water at ~15% per week which as the models we agree on show would manage reasonable under and over dosing.

Here is one conclusion of that study: "It is clear that most synthetic sea salts do not add substantial amounts of trace levels to aquaria when compared to the natural seawater available to the majority of hobbyists."

Does that matter or is it a distinction without a difference? natural seawater also has higher levels of industrial pollutants. I'm not sure what we can conclude from this.

But this is by the by. The point that I made is that it is cheaper and easier to manage these things at smaller water volumes by simply changing water regularly rather than testing for and dosing all of those elements in precise quantities which is the normal implication if you decide to stop changing water. Not testing and not changing water will always be cheaper but it doesn't sound like a high probability path to success particularly for someone new to the hobby.