Reasons for Doing Water Changes?

[dz6t]

I think you may just give up the notion that triton method equals to no water change.

 

[TbyZ]

Hey TI; I'm playing devils advocate for the 'no regular water changes Team' in this thread, to learn & understand & grind out the concept, so keep that in mind.

To clarify, Sanjey's system had only gone 5 years without water changes at the time of the video.

Yes, 5 years is quite substancial. He could do a 100% water change in stages over a week, then wait another 5 years to do the next water change.

His system is much older than that and will have cryptic sponges removing bacterioplankton and recycling a lot of the DOC released by algae and corals, converting it into nitrogen rich detritus and small amounts of inorgainic phosphate and inorganic nitrogen. Another thing going for him is the DOC released by corals promotes autotrophic microbial activity.

Yes, this is one aspect that I have argued will, if not totally negate the need for regular water changes, certainly reduce a tanks dependenancy on them.

We can't test for these various types of DOC yet so it may be tempting to think we can run a system without water changes but until we know how to test and mitigate the formation of refractory DOC it's and still add food to a closed system sooner or later refractory DOC is going to cause issues.

" Are they a substantial issue? Not sure." to quote Randy. Its a guess.
We're guessing if, & how much refractory organics might build up in the aquarium, & if they're toxic to a point of being a problem.

In regards to refractory organics - "There are alternative explanations for the persistence of marine DOM in the ocean. According to one of these hypotheses as microbes tend to be nutrient limited in ocean surface environments they are not able to utilise all DOM that is available as a substrate for growth, which therefore enables DOM to persist in the ocean on a seasonal timescale. (not likely a problem in an aquarium)

"It is suggested by another hypothesis that organic molecules in the ocean are so diluted that it is not likely they will encounter a microbe that has the ability to consume them, and this allows them to persist for long periods (Dittmar, 2015)." (again, not a likely scenario in the aquarium.)

What if the build up of refractory organics does occur in the aquarium, & they are toxic?
"In addition to the water's decoloration, another potential benefit of the ozone's reaction with aquarium water is the destruction of organic toxins. Many marine creatures secrete toxins that are designed to be harmful to other organisms. If these are allowed to build up in aquaria, they might become stressful for certain organisms. In addition to using activated carbon and skimming to remove them, ozone may also play a useful role."

"As discussed above, ozone's reaction with organic molecules involves fairly specific types of reactions, and it does not remove all organic materials from the water passing through the contact chamber. However, many toxins have very specific structures, being toxic specifically because they fit exactly into or onto some important biomolecule in a living organism, thereby interfering with its normal activity. Even a small chemical change will likely reduce the toxicity of even a very potent natural toxin.."http://reefkeeping.com/issues/2006-03/rhf/index.php#12 (thanks Randy)

Then there's UV sterilization.

 

[bif24701]

I change 33.3% every week or two in order to keep my water the best it possibly can be. I get about two water changes per box of IO salt. With a beautiful and easy to use RODI collection and salt mixing station makes water changes super easy. I use a python to pull the water out of my display tank and straight into a sink. Then I turn a valve and pump fresh mix water into my sump from the mixing station. I use a 25' hose and same pump that mixes the water and salt, Iwaki RTL40. It takes a little while for the Python system to remove the water from my system but filling with the Iwaki and 3/4" braided hose takes only a couple minutes. I see no down side to changing water and having it so easy really motivates me to do it regularly. My RODI has a float valve on the mixing station so it fills automatically. I just turn on the Iwaki pump and dump in two bags of salt. I add a few cups of additional MAG and let it mix a few hours until clear. That's all. The whole thing doesn't drip a single drop of water on the floor and total time actually doing actions other than just waiting for it to drain is only about 5 minutes of actual work. Keeps all parameters rock solid and water pristine. Cost doesn't seem significant to me considering what it would cost to add/use supplements to maintain the same water quality. Only additions I make to this system are Kalk and some vinegar, both of which are very very cheap.

 

[bif24701]

Perhaps you used an unsuitable gac.
ROX 8 is very good. I have never had a cyano problem so i don't know really.

I will only use BRS ROX .8 carbon because it's very low dust, highly effective and it doesn't otherwise affect the water chemistry.

 

[dz6t]

Hey TI; I'm playing devils advocate for the 'no regular water changes Team' in this thread, to learn & understand & grind out the concept, so keep that in mind.


Yes, 5 years is quite substancial. He could do a 100% water change in stages over a week, then wait another 5 years to do the next water change.


Yes, this is one aspect that I have argued will, if not totally negate the need for regular water changes, certainly reduce a tanks dependenancy on them.


" Are they a substantial issue? Not sure." to quote Randy. Its a guess.
We're guessing if, & how much refractory organics might build up in the aquarium, & if they're toxic to a point of being a problem.

In regards to refractory organics - "There are alternative explanations for the persistence of marine DOM in the ocean. According to one of these hypotheses as microbes tend to be nutrient limited in ocean surface environments they are not able to utilise all DOM that is available as a substrate for growth, which therefore enables DOM to persist in the ocean on a seasonal timescale. (not likely a problem in an aquarium)

"It is suggested by another hypothesis that organic molecules in the ocean are so diluted that it is not likely they will encounter a microbe that has the ability to consume them, and this allows them to persist for long periods (Dittmar, 2015)." (again, not a likely scenario in the aquarium.)

What if the build up of refractory organics does occur in the aquarium, & they are toxic?
"In addition to the water's decoloration, another potential benefit of the ozone's reaction with aquarium water is the destruction of organic toxins. Many marine creatures secrete toxins that are designed to be harmful to other organisms. If these are allowed to build up in aquaria, they might become stressful for certain organisms. In addition to using activated carbon and skimming to remove them, ozone may also play a useful role."

"As discussed above, ozone's reaction with organic molecules involves fairly specific types of reactions, and it does not remove all organic materials from the water passing through the contact chamber. However, many toxins have very specific structures, being toxic specifically because they fit exactly into or onto some important biomolecule in a living organism, thereby interfering with its normal activity. Even a small chemical change will likely reduce the toxicity of even a very potent natural toxin.."http://reefkeeping.com/issues/2006-03/rhf/index.php#12 (thanks Randy)

Then there's UV sterilization.

UV does not remove toxin nor DOM.

 

[Newb73]

My tank exchanges 200ml every 10 minutes for 12 hours a day.....at a grand total of about 8gpd of water to make the rodi water and a grand total of about $1.10 of salt per day.

 

[TbyZ]

My tank exchanges 200ml every 10 minutes for 12 hours a day.....at a grand total of about 8gpd of water to make the rodi water and a grand total of about $1.10 of salt per day.

How many gallons is your system?

 

[bif24701]

My tank exchanges 200ml every 10 minutes for 12 hours a day.....at a grand total of about 8gpd of water to make the rodi water and a grand total of about $1.10 of salt per day.

To me changing water seem cheap for all that you get. Have my own RODI and know exactly when filters/DI needs to be changed. I haven't had to replace any thing in the last 6 months where I changed one DI stage. Had both Triton and ICP-analyzing tests done and all parameters are exactly with in range.

 

[Randy Holmes-Farley]

A significant portion of DOC is refractory and resists being metabolized by anything. Dr. Haas, et al, found the only times DOC dropped to zero around reefs was in highly eutrophic systems completely taken over by algae and heterotrophic bacteria (presentation to our local reef club). The only other way I know of to remove the refractory DOC in our systems is with water changes.

Depends on what you men by refractory. If you define that as refractory to biological processes, then abiotic processes such as GAC, skimming, GFO, purigen, and other binders can remove many (but not all) of them.

Ozone, UV, and other oxidizers can convert some refractory organics into more biologically accessible forms.

If, by refractory, you mean resistant to all of these, then I agree, water changes are the only way.

 

[Randy Holmes-Farley]

That begs the question - what produces the refractory DOC, &, is there much if any in our aquariums?

I discuss organics here:

Organic Compounds in the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2004-10/rhf/index.htm

from it:

One interesting aspect of organic compounds in the ocean is that some have been there for thousands of years.1,3 Many organic compounds, especially in surface waters, are rapidly cycling between living organisms that consume and modify them, and the dissolved forms that are just floating about. Acetate, for example, can have a turnover rate as high as once per day on average in the water column, and once per hour or two in pore water inside sediments.3

With each turn of this cycle, some of these organic materials become more and more refractory. That is, they become less and less palatable to organisms, and are turned over more and more slowly. Eventually, some remain that are largely resistant to further biodegradation and processing, and these can then stay as DOM for many thousands of years. Essentially, they are the waste that is left after every organism has had its shot at using them.

The pathways for degradation of such refractory molecules are not well known, but likely reflect some rare biological events (rare bacteria encounter them, they encounter a rare enzyme, or they are acted upon by an enzyme that does not normally process them, etc.). The long term degradation likely also includes physical and chemical processes, such as oxidation by oxygen, ozone, or other oxidizing agents, and being hit by appropriate radiation (UV, x-rays, gamma rays, etc.).

 

[Newb73]

I discuss organics here:

Organic Compounds in the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2004-10/rhf/index.htm

from it:

One interesting aspect of organic compounds in the ocean is that some have been there for thousands of years.1,3 Many organic compounds, especially in surface waters, are rapidly cycling between living organisms that consume and modify them, and the dissolved forms that are just floating about. Acetate, for example, can have a turnover rate as high as once per day on average in the water column, and once per hour or two in pore water inside sediments.3

With each turn of this cycle, some of these organic materials become more and more refractory. That is, they become less and less palatable to organisms, and are turned over more and more slowly. Eventually, some remain that are largely resistant to further biodegradation and processing, and these can then stay as DOM for many thousands of years. Essentially, they are the waste that is left after every organism has had its shot at using them.

The pathways for degradation of such refractory molecules are not well known, but likely reflect some rare biological events (rare bacteria encounter them, they encounter a rare enzyme, or they are acted upon by an enzyme that does not normally process them, etc.). The long term degradation likely also includes physical and chemical processes, such as oxidation by oxygen, ozone, or other oxidizing agents, and being hit by appropriate radiation (UV, x-rays, gamma rays, etc.).

Another score for ozone use!

 

[Newb73]

How many gallons is your system?

265 gallons

 

[Hans-Werner]

ICP tests are now available to get exact figures on all major, minor & trace elements

Sure? I think most ICP-OES analysis can detect a more or less severe overconcentration of many elements but it can´t detect how low most trace elements really are. Most ICP-EOS analysts give green light if they can´t detect most of the essential trace metals.

It may be a very unlikely event but the corals will die if essential trace metals like iron, manganese, copper, nickel or zinc are present in concentrations unavailable to the corals. In most tanks ICP-OES will not find all of these metals, in many tanks it will find none or only one or two.

 

[Scott Campbell]

My tank is 30 years old and I have never been a big proponent of water changes. I went about 10 years without a water change and for a while even experimented with minimal feedings just to see how self-sustaining the tank could become. My tank is heavily infested with sponges and tube worms and I have always grown large amount of macro algae.

That said - my corals grow much more quickly with small water changes. And once I started with the Triton tests I realized (ironically perhaps) that small water changes with the salt I use was the most cost effective way to deal with most of the Triton test dosing recommendations.

I guess my main observation over the years is that nothing is really static in an aquarium. I'll notice a sudden increase in certain worms, microfauna or algae types until water conditions change and the worm or algae populations diminish. I expect it is often the extra growth of certain algae or microfauna that causes the depletion of whatever nutrients triggered the growth in the first place. My point being the tank always seems to be self-adjusting and self-regulating. So trying to understand what to dose is difficult. It is a moving target.

I don't enjoy doing water changes, I prefer to dose what the tank needs if possible, I use ROX carbon and I have lots of filter feeders to take up organics. But I do water changes because my salt is a cost effective way to replenish what is being depleted, my corals grow faster and I recognize I just don't know enough to dose exactly what the tanks needs.

 

[jda]

What about Chloride Ions? Can those get too high if there are no water changes? I have always wondered. Does anybody test for them?

 

[TbyZ]

Sure? I think most ICP-OES analysis can detect a more or less severe overconcentration of many elements but it can´t detect how low most trace elements really are. Most ICP-EOS analysts give green light if they can´t detect most of the essential trace metals.

It may be a very unlikely event but the corals will die if essential trace metals like iron, manganese, copper, nickel or zinc are present in concentrations unavailable to the corals. In most tanks ICP-OES will not find all of these metals, in many tanks it will find none or only one or two.

ICP tests are useful fo
Well of course the trace elements you mention, if critically low in an aquarium, will always be low if the only method of replenishing them is via regular water changes. I dose all of them, or at least the ones that are apparently important.

In regards to other elements either having low or high concentrations in an aquarium, as indicated by ICP tests, that can be the case whether regular water changes are performed or not. ICP test are important no matter what method of tank maintenance one chooses.

 

[TbyZ]

What about Chloride Ions? Can those get too high if there are no water changes? I have always wondered. Does anybody test for them?

people who dose only two part - sodium bicarbonate & calcium chloride have this problem because after the carbonates are used the sodium is left behind, as is the chloride after the calcium is used up. Because regular water changes cannot replenish the carbonates & calcium to the degree they are taken up, in most cases, dosing becomes necessary. There are ionically balanced supplements which also include non sodium chloride salts, & adding them keeps the salts in the proper ratio. Using a calcium reactor also solves the problem, as does dosing calcium hydroxide (kalkwasser).

 

[TbyZ]

My tank is 30 years old and I have never been a big proponent of water changes. I went about 10 years without a water change and for a while even experimented with minimal feedings just to see how self-sustaining the tank could become. My tank is heavily infested with sponges and tube worms and I have always grown large amount of macro algae.

That said - my corals grow much more quickly with small water changes. And once I started with the Triton tests I realized (ironically perhaps) that small water changes with the salt I use was the most cost effective way to deal with most of the Triton test dosing recommendations.

I guess my main observation over the years is that nothing is really static in an aquarium. I'll notice a sudden increase in certain worms, microfauna or algae types until water conditions change and the worm or algae populations diminish. I expect it is often the extra growth of certain algae or microfauna that causes the depletion of whatever nutrients triggered the growth in the first place. My point being the tank always seems to be self-adjusting and self-regulating. So trying to understand what to dose is difficult. It is a moving target.

I don't enjoy doing water changes, I prefer to dose what the tank needs if possible, I use ROX carbon and I have lots of filter feeders to take up organics. But I do water changes because my salt is a cost effective way to replenish what is being depleted, my corals grow faster and I recognize I just don't know enough to dose exactly what the tanks needs.

Thanks for the input SC, very informative. And I don't doubt your observations are accurate, or that regular water changes are the way to go for you.

Two questions if I may SC ?

1. Do you dose anything in the way of elements at all ? including for calcium & alkalinity?

2. What elements do you believe are in the salt mix you use, that makes the positive difference to your tank, that wouldn't be, or couldn't be in a dosing suppliment, such as the one I'm using, Aquaforest, for example?
A.F. has three parts - sodium bicarbonate, calcium chloride & non sodium chloride salts plus all the other minor & trace elements, at least the apparently important ones.
I can't imagine that there is anything in your container of salt that isn't in A.F ?

 

[Coronus]

My tank always looks refreshed after a nice water change. Its like a bath for my pets. New water going in...yea!!!
It would totally suck to shower and live in the same water 100% of the time. Never clean water coming in. A filter cleaining it, but still, not truely clean water. Untouched, unsoilded, un processed, and poop free!! What fish would not love that. What coral would not love that. Would anyone reading this rather drink NEW clean water or clean water?? You pick!

 

[TbyZ]

My tank always looks refreshed after a nice water change. Its like a bath for my pets. New water going in...yea!!!
It would totally suck to shower and live in the same water 100% of the time. Never clean water coming in. A filter cleaining it, but still, not truely clean water. Untouched, unsoilded, un processed, and poop free!! What fish would not love that. What coral would not love that. Would anyone reading this rather drink NEW clean water or clean water?? You pick!

you do realise that the water you use to make up your saltwater was from a dam or lake that had fish pooping in it?
And that you run it through a RODI unit because it still has yucky stuff in it?
So Coronus, your actually using "the same water 100% of the time. Never clean water coming in. A filter cleaining it, but still, not truely clean water."