But everyone does water changes...

[reverendmaynard]

I would like to point out what looks to me to be a major flaw in one of Mr. Wilson's criticisms of water changes. That being the mention of the impurity of the base water used to create the WC water in the first place.

IF you have that problem (using tap, regular RO, or RO/DI with a depleted resin) and your "fresh" water contains impurities, you are adding those impurities as top off water every single day. They may get removed by some export means, but that is hardly proven. Just for a second, let us assume that they are not and look at the effects of adding these compounds to a tank without any water changes...

You have a 100g tank. It evaporates 1 gal per day. You replace that gallon with water that contains 1ppm of compound x. Now, since you originally filled the tank with this water, you started with 1ppm. After 100 days of evap replacement, you will be up to 2ppm. For every 100 days, the concentration rises by an additional 1ppm. After 2 years, you'd have around 8ppm of compound x. Is this a problem? Who knows? Will regular WCs eliminate this compound? Of course not. Will they keep the level at a finite level that may prevent the concentration from reaching problematic levels? Quite possibly. 30% WCs monthly would limit the max concentration to about 2ppm (at 2ppm, removing 30% of the water would remove 60 "parts", replacing it with 30 "parts", and then adding 1 "part" per day for 30 days.) At the end of 2 years, the tank that gets WCs would still be at 2ppm, the tank wiith no changes is at 8ppm. The point being that if you are using less than pure "fresh" water, your need for WCs would be greater than if it's totally pure.

See, I don't believe in the notion that there are no unknowns in a reef aquarium. First, I think that that greatly overinflates the extent of the scientific knowledge that even the most knowledgable expert currently has. IMO, current scientific knowledge about reef tank husbandry amounts to no more than a thimble full in the ocean compared to all there is to know. Second, it's absurd to think that even 1% of reef tank owners have all of the available knowledge, or even enough to truly make anything more than an educated guess about their water quality. Fresh made artificial SW may not be the best thing in the world for your livestock to flourish in, but, IMO, it is much more of a known entity, as compared to water that's been in your tank for 2 years. As Gary Majchrzak points out in his post containing Eric Borneman's myth article, no one can possibly know all of the compounds that may be in their water. WCs are the best way to keep your tank near some sort of baseline for ALL compounds. Relying on any/all of the export mechanisms sited in the complete absence of WCs is ignoring the fact that there may be potentially harmful compounds that are not exported in sufficient quantities to insure they do not become problematic.

I see you site RHF in his various articles as not showing WCs to be a good means of export for nitrate, phosphate, etc., however I didn't see you mention that RHF himself performs continuous WCs of approximately 1% per day.

 

[Arman]

Any underwater plants or macro-algae may remove many of possible trace elements out of the water, harmful as well as usefully they trap everything in their biomass even coper, lead, titanium, all was found during chemical analysis of submerged plants cells.

So may be those who want to research the ways that would allow to skip large amount of water changes should work in this direction.

Theoretically Ocean is huge amount of water but over millions of years no one was doing WC. This means it remains clean only due to export, and somehow manages to export even toxic heavy metals.

How much those methods applicable in the home aquarium is another issue.

I have too little experience with reef aquarium to judge.

 

[Glass Oceans]

<a href=showthread.php?s=&postid=8929127#post8929127 target=_blank>Originally posted</a> by Gary Majchrzak
That's your opinion and you're entitled to it.


The fact of the matter is that the majority of reefkeepers are not as knowledgable as you appear to be, mr.wilson, and very few have the facilities that Morgan Lidster has available to him at 'Inland Aquatics'.
The water change (executed properly) thus remains perhaps the most practical method for the majority of reefkeepers to avoid the accumulation of harmful compounds in their aquarium.

Inland Aquatics sells a lot of stuff. In Salt water. I think they are doing more water changing than most of us.

 

[mr.wilson]

Every aquarium has its' own unique properties and every aquarist has their own unique expectations. I took my seahorse tank down a while ago because I didn't have time for water changes or even top-ups.

It was a very basic tank that did exactly what I wanted it to do, keep a pair of seahorses happy. It ran with just circulation from a powerhead and had only 27 watts of light, plus whatever indirect sunlight it received. I had a pair of Kuda seahorses in there along with a few leftover coral frags from clients tanks.

The small nature of the aquarium made the use of a protein skimmer, calcium reactor, refugium, and even surface skimming cost and space prohibitive. After weighing my options, I decided that this is a case where water changes are more cost effective. The $1,500.00 I saved on equipment would pay for years of salt, a situation that only applies to small tanks. The 600 gallon tank I service would not hold up to this model, and I couldn't change that much water if I wanted too.

I was changing half of the water every week, until I couldn't fit it into my schedule. A major export like this would match or surpass the export methods that I employ in larger tanks. The calcium and DKH levels were always the same as freshly mixed saltwater, so there was no need for chemical dosing either. I kept a bag of carbon behind the rocks as a fail-safe. The seahorses enjoyed hanging on the tree sponge and gorgonian, and the macroalgae encouraged the growth of fresh live food (zooplankton). No refuge from herbivores and omnivores was required, so the tank was the "refugium" for all life in the closed system.

At first, I stopped doing water changes (when my daughter was born). Nitrate started to climb, but seahorse tanks aren't harmed by this. The tank never had algae on the glass, before or after, due to the low lighting.

I considered doing batch denitrification, a process whereby a large quantity of water is removed from the tank and stored in a dark bucket with no flow and a deep sand substrate. The water is stored like that for month, or until the bacteria remove the nitrate. With a 15 gallon tank, I could have six, 5 gallon buckets of water in the denitrification process, and always have nitrate-free water available. As one bucket is exported, an "older" processed bucket could be imported. The benefit of the procedure is no more salt costs, but the work was about the same, and it only removed some harmful agents (primarily nitrate).

My daughter is at the age where she can appreciate a tank now, so I'm working on a 60"L x 10"W x 36"H reef tank for her room. It should be done in a couple of months. I'm going to use space in the basement to have an oversized refugium, RDSB, and extra holding tanks (50 gallon drums) for greater water volume. I think large holding tanks are going to be the way of the future, but I don't expect to see them in large urban centers where space is at a premium.

 

[BeanAnimal]

<a href=showthread.php?s=&postid=9239332#post9239332 target=_blank>Originally posted</a> by Arman


Theoretically Ocean is huge amount of water but over millions of years no one was doing WC. This means it remains clean only due to export, and somehow manages to export even toxic heavy metals.

There has of course been some "export" via the movement of tides and the movement of the oceans on the planet. Some of the "stuff" gets encapsulated in conglomerate rock, some of it undergoes chemical change or combination with other things.

However, for the most part what gets put in there stays in there. The ocean and it's substrate are a massive sink for just about everything.

Consider the amount of heavy metals contained in any single large body that has hit our planet. How much do you think was released when the Dino extinction event happened? What about the hundreds of thousands of other natural events that have loosed billions of tons of heavy metals, radioactive materials and greenhouse gases from the earths crust and mantle or objects that have struck the earth?

Not that we SHOULD pollute the water haphazardly and not that we can not have an effect on our environment sometimes, but in the scheme of things...

So no no water changes, but how much food coloring do you have to drip into lake Erie before you start to notice a color change?

Our captive reefs only resemble the real ocean. The economies of scale are just not the same. They are two totaly seperate type of ecosystems that share more differences than they do similarities.

 

[mr.wilson]

While I certainly don't condone the use of inferior source water, I'm the first to admit that it's the norm. Top-off for evaporation will not exceed the quantity added with regular water changes, so the point is moot.

I believe that the removal of impurities through systemic export methods has been proven. Dr. Rons study didn't measure every known and unknown agent out there, but it illustrated a fairly uniform catch-all of what we can measure. This was shown to be the case with all of the export methods he tested, and has been proven elsewhere to be the case with chemical filtration like molecular absorption media and ion exchange resins.

I would like to see a study where the quantity of "bad stuff" is compared between exported water from regular water changes, and exported water from regular skimmer cup cleaning, xenia harvesting, and macroalgae harvesting. One could also compare a bioassay of spent carbon, polyfilters and ion exchange resins, to the yield from a basic water change. I don't think there's much "bad stuff" in a bucket of tank water when you compare it.

I think the study would show water changes removed less "bad stuff" and imported more "bad stuff" than the other methods listed. I also think that the study would show that regular water changes have a higher operating cost and are more time consuming.

While it's true that we can't find and classify every element in our water, it's safe to say that we have a knowledge of their existence. I can't measure the quantity of secondary metabolites in a tank, but I can accurately gauge the overall condition of the aquarium and ascertain if there are growth limiting factors or pathogens present. Coral and fish act as the ultimate test kit. The growth of nuisance algae is another warning sign that we have at our avail.

Water treatment plants have employed freshwater fish like elephant nose and black ghost knives to test for unknowns in the water. These two fish have electrical systems that they use for navigation in dark muddy water. Their electrical signal is altered with the most minute change in water quality. They cannot tell us what is in the water, or if it is harmful, but we can measure change.

I wasn't trying to put words in Randys mouth. He's a proponent of water changes, and has written articles to back up his opinion. My use of his article was to illustrate my point that water changes are not an efficient method of nitrate and phosphate export. Water changes remove "bad stuff", but not well enough to put them on his list of methods that even included some that he didn't have much knowledge of.

Randys cowfish (RIP) gave him added reason to do water changes. The tetrodotoxin generated by cowfish is a known toxin, but we cannot measure it, nor the extent of its' impact on the aquarium. Randy has a yellow tang with a growth defect (dorsal fin) that doesn't resemble typical marine fish ailments, other than perhaps lateral line disease. Lateral line disease is a symptom, not an actual disease. There are a number of causative agents that could contribute to such a condition. It could be a result of long-term exposure to the toxin. The sudden death of the cowfish could also be attributed to life in a closed system, with or without water changes.

The point I'm trying to make, is we don't fully understand the unknowns, but we know they are there and that there is a need to remove them. Water changes will accomplish this, but they are far down the list of efficient methods. I don't mean to single Randy out, he just happens to be someone with a tank diary that many of us are familiar with.

Wholesale and mariculture facilities such as Inland Aquatics, export water every time they sell something, but a very small amount. They probably spend six months feeding a coral to grow it to a marketable size. The quantity of water shipped with the coral is minute compared to the amount of food that has been imported to achieve the growth. A pint of imported food cannot be removed by a pint of exported water. A two hundred gallon holding tank might lose 5 gallons of water on shipping day, every six months. They export just as much water with spillage and algae scrubbers.

 

[Arman]

I did some calculation here about the case with 100g tank with 1ppm input per 100 days. Regarding to my calculation by changing 40% of water every 100 days, you can keep unknown to 1.5ppm-2.5ppm.

Spending at the same time just 40g of saltwater per 100 days, instead of spending 90g doing 30% changes every month.

Every water change done once per 100 days you remove 100 and put 40 units of unknown.

 

[BeanAnimal]

Randy Holmes Farley (over in the chem forum) and others have published the dilution studies that show the difference intermitant regualr large wter changes and continuois small water change methods.

The continuous change method works out very well. Once you get ahead of the pollution problem, you stay ahead. There are no swings backand forth like there are with the scheduled water changes.

 

[reverendmaynard]

<a href=showthread.php?s=&postid=9246692#post9246692 target=_blank>Originally posted</a> by Arman
I did some calculation here about the case with 100g tank with 1ppm input per 100 days. Regarding to my calculation by changing 40% of water every 100 days, you can keep unknown to 1.5ppm-2.5ppm.

Spending at the same time just 40g of saltwater per 100 days, instead of spending 90g doing 30% changes every month.

Every water change done once per 100 days you remove 100 and put 40 units of unknown.

Actually, the equilibrium point would be closer to 3.5ppm (40gal out *3.5units=140units, 40gal wc in*1 unit/gal + 100gal top off *1 unit/gal=140units.) The larger point still stands IMO, that doing some kind of regular water change will reach an equilibrium point even if you are putting the same contaminant back in with the water change. Of course, that is contingent on there being 0 export of said contaminant. If in fact there is an export method in place that exports faster than the top off is replacing it, than Mr. Wilson would be right in that doing the water change would increase the level of contaminant. I for one believe that it's safer to do the water changes, putting a ceiling on the level that contaminants can reach, rather than hope that all possible contaminants are being exported/neutralized within the system. JMO.

 

[mr.wilson]

This is the article by RHF that justifies his 1% per day exchange. If I were to do water changes, I would do the same, using a Spectrapure Litermeter 3.

That would equal 6 gallons per day for my 600 gallon tank, so I would have to mix up a 50 gallon drum of fresh salt water every week. The cost of such an undertaking would represent the highest operating expense, including hydro.

I respect others wishes to continue to do regular water changes, but I don't find value for money in the practice.

 

[MiddletonMark]

50 gallons of saltwater is what? $15?

You can run water movement + lighting on a 600g tank for under that?

IME, salt expense is pretty small in comparison to Ca/Alk supplimentation or running electrical costs.

 

[reverendmaynard]

My feeling would be similar to MiddletonMark's. When you're running a 600 gallon tank, $60 bucks a month seems like a relatively small investment.

Of course, if you believe that water changes are not beneficial and/or possibly bad, than obviously any investment at all doesn't make sense. If you believe as I do that there are more than likely benefits that outweigh the negatives, $60 a month seems like a very small investment towards keeping that tank and livestock that cost in the tens of thousands (perhaps even 6 digits?) of dollars going in tip-top condition.

I would certainly not try to change anyones mind, especially someone as advanced in knowledge as you seem to be, Mr. Wilson. I'm just trying to present an alternate viewpoint for those who haven't yet made up their minds on the subject.

 

[mr.wilson]

Up here in Canada a 160 gallon mix of Reef Crystals is US$90.00 (Big Al's). My hydro consumption for that tank, according to the RC calculator is US$85.00.

If someone offered you a product that was guaranteed to improve your water quality by 1%, with an operating cost increase of 80%, I doubt you would jump at the chance.

Many aquarists forego the use of polymeric absorbents and ion exchange resins like Polyfilters and Chemipure. These products will increase water quality by a factor far greater than 1%, at a fraction of the cost. Upgrading a refugium or Protein skimmer has a high upfront cost, but low operating cost. I feel these improvements will yield more than a 1% impact.

Cost isn't the primary concern here, but your least effective method of water quality management shouldn't be your most expensive.

Once again, I agree that regular water changes help, but maintain that they are inefficient means.

 

[MiddletonMark]

IMO, most of these other export mechanisms are not cheap, often one-time uses [like salt].

We also have to talk about scale ... that $45 bucket of Reef Crystals goes a long way on my 58g tank. Compared to a $15 polyfilter or other $10+ filters that I'd go through in a week or two ... to my tank-size, the bucket of salt that allows me a 100% w/c for 3 months [if I decide to go that route] is pretty cheap in comparison IMO. [as most chemical media will be useless within a month IME].

Looking at efficiency this way, I guess I don't see a benefit to chemical media. [Carbon + other filter would be a greater cost for my 58 monthly than salt for 100% monthly changes, by my figuring].

 

[reverendmaynard]

Well, your costs for salt are certainly far higher than mine. I can get 200gals of IO for $32 at a LFS.

By "hydro", do you mean electricty?

1% water quality improvement is not a very accurate figure, IMO. In this article by RHF (http://reefkeeping.com/issues/2005-10/rhf/index.php), figure 10 shows the cumulative affects of 1% daily water changes on nitrate levels with a constant rate of input. You can see that after one year the level is only around 25% of what it would be with no changes at all, a 75% improvement. Now, nitrate export/reduction is a well known entity in reef aquariums, and can be accomplished, and tested for, with near 100% effectiveness so you're not going to see anywhere near that level of improvement with regards to nitrate. However, if there was a mystery compound that is both completely unaffected by any known export mechanism and is either constantly added to or constantly produced within the tank, you would see that level of improvement.

 

[guntercb]

Mr Wilson,

Thanks for giving us the history on your sea horse tank.

I cannot imgine the 600 gallon tank you maintain. I would not want to do water changes on that either. Ouch.

I would like to do a 1% water change a day too, but I don't have a sump room and no way to automate a water change with my current system. I do a once a week water change of 5 gallons from my 120, but I am sure I am not exporting much. But I hope I am helping to keep the system "more stable". I do think I export more "stuff" in my skimmer and filter bags than my water change. But I just cannot give up my water change. Just seems weird. Never planned the system to not do water changes.

Maybe one day, I will try a system that goes long periods of time between water changes. I don't know if I would do zero water change tank.

FYI..

In his article, Julian Sprung says, "In many cases I have set up these aquariums with no water change at all (for several years). " Here is the article:

http://www.advancedaquarist.com/issues/sept2002/feature.htm

Cheers,
Chris

 

[davidryder]

Interesting debate! Has anyone considered the degradation of synthetic sea salt over time? Over time synthetic sea salt loses it's ability to buffer PH. I think the replacement of that salt through water changes is by far the cheapest method of restoring buffering ability. Am I missing something?

 

[Questin]

It is not a water change because you are not replacing any of the chems found in salt water, that is why people do not replace evaporated water with salt water. If a person did that, they would kill everything in the tank because the salt measurement would go thru the roof.

 

[mr.wilson]

<a href=showthread.php?s=&postid=9249448#post9249448 target=_blank>Originally posted</a> by reverendmaynard
Well, your costs for salt are certainly far higher than mine. I can get 200gals of IO for $32 at a LFS.

By "hydro", do you mean electricty?

1% water quality improvement is not a very accurate figure, IMO. In this article by RHF (http://reefkeeping.com/issues/2005-10/rhf/index.php), figure 10 shows the cumulative affects of 1% daily water changes on nitrate levels with a constant rate of input. You can see that after one year the level is only around 25% of what it would be with no changes at all, a 75% improvement. Now, nitrate export/reduction is a well known entity in reef aquariums, and can be accomplished, and tested for, with near 100% effectiveness so you're not going to see anywhere near that level of improvement with regards to nitrate. However, if there was a mystery compound that is both completely unaffected by any known export mechanism and is either constantly added to or constantly produced within the tank, you would see that level of improvement.

Sorry, it's the language barrier. We (your neighbors, or neighbours as we spell it, to the north) call our electricity bill a "hydro" bill, as in hydro-electric. I think "hydro" refers to a different kind of consumable in the US (Canada supplies the US with both ).

A 1% water change improves water quality by 1% daily, or 30% monthly, assuming there is a deficit. You will only experience greater export than 1% monthly, if the import is less than 1% daily. In other words, a problematic tank with a heavy bioload and poor filtration and husbandry will only be maintained, not reduced by the 1% daily water change. The nitrate load in the model is arbitrary, but falls within a reasonable guesstimate; however, this forum is full of stories of 25% weekly water changes and unshakable 40ppm nitrate.

You could apply the same model to any method of nutrient export. The other methods discussed in this thread will remove quite a bit more than 1% per day. If we use the same nitrate load from our model, the reduction via these methods would be 100%, and would be accomplished in a fraction of the time. It's easier to compare apples to apples and just look at daily performance, without factoring in accumulative results.

Once again, I'm not disputing RHF's data or the belief that RWC's can effect a change. My point is, there is proof that they are not cost effective, efficient means of export. There is also data showing that they import impurities into the system that will accumulate. Scientific research and anecdotal observations corroborate the fact that sufficient means of export and supplementation currently exist in a properly set-up reef tank. Water changes are therefore redundant.

 

[mr.wilson]

<a href=showthread.php?s=&postid=9258451#post9258451 target=_blank>Originally posted</a> by mr.wilson

I used Reef Crystals in my example because I wanted to use a brand that din't add impurities. A 160 gallon bucket of IO is US$52.00 locally. I drive down to Buffalo and pay US$28.00 for a 200 gallon mix of IO, but that's wholesale, and not typical of what my client would have to pay.

Carbon retails for US$200.00 for 40 pounds, and I can assure you it lasts a lot longer than the bucket of salt will, for any sized tank.

Sorry, it's the language barrier. We (your neighbors, or neighbours as we spell it, to the north) call our electricity bill a "hydro" bill, as in hydro-electric. I think "hydro" refers to a different kind of consumable in the US (Canada supplies the US with both ).

A 1% water change improves water quality by 1% daily, or 30% monthly, assuming there is a deficit. You will only experience greater export than 1% monthly, if the import is less than 1% daily. In other words, a problematic tank with a heavy bioload and poor filtration and husbandry will only be maintained, not reduced by the 1% daily water change. The nitrate load in the model is arbitrary, but falls within a reasonable guesstimate; however, this forum is full of stories of 25% weekly water changes and unshakable 40ppm nitrate.

You could apply the same model to any method of nutrient export. The other methods discussed in this thread will remove quite a bit more than 1% per day. If we use the same nitrate load from our model, the reduction via these methods would be 100%, and would be accomplished in a fraction of the time. It's easier to compare apples to apples and just look at daily performance, without factoring in accumulative results.

Once again, I'm not disputing RHF's data or the belief that RWC's can effect a change. My point is, there is proof that they are not cost effective, efficient means of export. There is also data showing that they import impurities into the system that will accumulate. Scientific research and anecdotal observations corroborate the fact that sufficient means of export and supplementation currently exist in a properly set-up reef tank. Water changes are therefore redundant.