What is accumulated and what is depleted in a reef tank after long (months) period of no water change

[Koty]

What is accumulated and what is depleted in a reef tank after long (months) period of no water change?
My DT (about 110 g) is rather standard: I have a Chaeto refuge, bio pellets, and GFO reactors, a skimmer (and until recently a UV sterilizer) and I do not do any water changes. My corals mostly LPS seem to look good. Aiptasia doing very well. Fish are heavily fed and are healthy including a Bengai cardinal pair that spawns every 45 days
Is there any data on specific organic or non-organic compounds? I am not referring to any of the elements we can supplement.
I dose two-part, trace elements , K and Iodine (TLF), Fe (Seachem) as well as sponge power (KZ, hoping it supplements silica to sustain sponge growth)

 

[gbroadbridge]

I see a rabbit hole - hope you're not on horseback.

Well done with the Aiptasia

 

[sixty_reefer]

Is your tank stable? I don’t believe there is any data available on the subject

 

[Randy Holmes-Farley]

I agree you'd need to generate data on your system if you wanted to know exactly what is happening, and some things you cannot test for. The beauty of water changes is that one does not need to know what is being added or removed.

Things that can accumulate are:

1. Organics that come in with foods, are produced by organisms in the tank, or are released from plastic materials. Toxins, yellowing compounds, and others.

2. Inorganic ions that are added in excessive amounts from foods, pl and other additions relative to demand. By ICP, many folks see certain elements accumulate from these processes.

3. Organometallic compounds that may be introduced without knowing it, such as tin compounds leaching from plastics.

 

[taricha]

hey @Lasse what did you catch accumulating in your long time of no large water changes?

 

[Lasse]

A picture (or several) is better than words

Tin - no dosing Red point - last WC (80 %) was done 3 days before 2018-01-17

Aluminium - use of Al based phosphate removers now and when Red point - last WC (80 %) was done 3 days before 2018-01-17

Copper -Red point - last WC (80 %) was done 3 days before 2018-01-17

Sodium - regular dosing Core 7 Red point - last WC (80 %) was done 3 days before 2018-01-17

Calcium - Red point - last WC (80 %) was done 3 days before 2018-01-17. Normally regulated with help of last IPC

Magnesium - regular dosing Core 7 Red point - last WC (80 %) was done 3 days before 2018-01-17. Normally regulated with help of last IPC

Potassium last WC (80 %) was done 3 days before 2018-01-17 in the beginning regulated with help of last IPC - but nowadays - no regulation

Bromide. Red point - last WC (80 %) was done 3 days before 2018-01-17 Normally regulated with help of last IPC. Candidate for regular dosing in the future Setpoint 62 mg/L

Bor. Red point - last WC (80 %) was done 3 days before 2018-01-17 From 2021-03-23 regular dosing - before that dosing after previous ICP result Red point - last WC 2018-01-17 Green point - start regular dosing

Strontium Red point - last WC (80 %) was done 3 days before 2018-01-17 Regular dosing

Sulphur Red point - last WC (80 %) was done 3 days before 2018-01-17

Lithium Red point - last WC (80 %) was done 3 days before 2018-01-17 Normally regulated with help of last IPC. Candidate for regular dosing in the future Setpoint 200 mg/L

Nickel Red point - last WC (80 %) was done 3 days before 2018-01-17 No dosing whatever Setpoint 5ppb

Molbyden Red point - last WC (80 %) was done 3 days before 2018-01-17 Normally dosing after last ICP Setpoint 12 ppb

Zink Red point - last WC (80 %) was done 3 days before 2018-01-17 No dosing whatever Setpoint 0-5 ppb

Manganese Red point - last WC (80 %) was done 3 days before 2018-01-17 Normally dosing after last ICP Setpoint 0-3 ppb

Iodine Red point - last WC (80 %) was done 3 days before 2018-01-17 regular dosing setpoint 30-90 ppb

Barium Red point - last WC (80 %) was done 3 days before 2018-01-17 No dosing. I have one result from 2022-03-31 that´s even higher. Have used GFO from ATI lately (since the upgoing curve)

Silicon Red point - last WC (80 %) was done 3 days before 2018-01-17 The reason for this WC was to bring down the Silicon concentrations, The source was Sera Siporax which was removed a week before. The value now is a little to high - around 900 ppb the last (not shown test) May be a indicator for a WC in the future

Vanadium and Iron is regular dosed - but have never shown up in the test

The other

I also dose rubidium but have that analysed at Oceamo. Between 150-200 pbb

I´ll think that these graphs will crash some myths.

This video show how the aquarium have developed during the same time



Sincerely Lasse

 

[Koty]

OK, based on the answers, we can maintain a reef tank w/o regular WC and to a good aproximation if we are careful enough nothing significant will accumulate. We can also assume that there is no carbon based compound that can accumulate as they will always be a bacteria that can utilize it. So we are left with trace elements (as the others we can monitor). Some that are needed and may get depleted and some that can accumulate (I include heavy metals). Application of GAC and metazorb comb8ned with dosing trace elements can take care of these. So to stay away from being anecdotal and misleading, avoiding water changes is an option to consider that yet needs careful planning. Primarily, you need a system with ample and diverse export methods and analyze what you can. Dosing IMO should be three part to minimize changes in salt concentrations.

My last WC was 8 months ago, but my tank is mostly LPS. Does anybody with an SPS dominant reef that runs W\O WC?

 

[gbroadbridge]

OK, based on the answers, we can maintain a reef tank w/o regular WC and to a good aproximation if we are careful enough nothing significant will accumulate. We can also assume that there is no carbon based compound that can accumulate as they will always be a bacteria that can utilize it. So we are left with trace elements (as the others we can monitor). Some that are needed and may get depleted and some that can accumulate (I include heavy metals). Application of GAC and metazorb comb8ned with dosing trace elements can take care of these. So to stay away from being anecdotal and misleading, avoiding water changes is an option to consider that yet needs careful planning. Primarily, you need a system with ample and diverse export methods and analyze what you can. Dosing IMO should be three part to minimize changes in salt concentrations.

My last WC was 8 months ago, but my tank is mostly LPS. Does anybody with an SPS dominant reef that runs W\O WC?

You probably can, however I doubt the cost to benefit ratio will work in your favour as it is likely you are spending more on expensive trace elements and ICP tests then you would ever have spent on salt.

One ICP test is equivalent to one 2/3rds of an RS blue bucket for me.

Not to forget that unless you never acclimatise a fish or a coral you are inevitably making small water changes along the way.

 

[blaxsun]

Not SPS-sominant, but my SPS are all doing great in my tank without regular water changes (I perform a 10% change about every 4 months).

 

[Sean Clark]

You probably can, however I doubt the cost to benefit ratio will work in your favour as it is likely you are spending more on expensive trace elements and ICP tests then you would ever have spent on salt.

One ICP test is equivalent to one 2/3rds of an RS blue bucket for me.

Presuming they have a small tank this ideology would be correct.

When applied to a larger tank this position begins to lose the economic argument.

 

[Koty]

You probably can, however I doubt the cost to benefit ratio will work in your favour as it is likely you are spending more on expensive trace elements and ICP tests then you would ever have spent on salt.

One ICP test is equivalent to one 2/3rds of an RS blue bucket for me.

Not to forget that unless you never acclimatise a fish or a coral you are inevitably making small water changes along the way.

I agree but first I don't think you need regular icp tests mainly because they are costly and the data on trace elements has marginal accuracy. Second is the fact that wc is also hard labor and there is the fear from the wrath
of my wife if a drop of seawater touches the living room furniture.

 

[Lasse]

The red point in my charts is when I did the last huge WC (80 %). I started with no regular WC much earlier in april 2017. Between the second and third point in most of my charts.

IMO - WC is not a good tool to add trace elements in a mature and fully grown reef aquarium - you need additives in any case IMO.

Sincerely Lasse

 

[Randy Holmes-Farley]

We can also assume that there is no carbon based compound that can accumulate as they will always be a bacteria that can utilize it.

I do not believe that is an accurate assumption. It is not true in the ocean.

Organic Compounds in the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com

One interesting aspect of organic compounds in the ocean is that some have been there for thousands of years. 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.

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.).

 

[Randy Holmes-Farley]

OK, based on the answers, we can maintain a reef tank w/o regular WC and to a good aproximation if we are careful enough nothing significant will accumulate.

Not sure what that is based on.

What does "careful enough" mean?

 

[Lasse]

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.

IMO - this the cause of "yellowing" of the water in a reef aquarium and it will be produced rather fast

The long term degradation likely also includes physical and chemical processes, such as oxidation by oxygen, ozone, or other oxidizing agents,

This - IMO - you can see by using ozone and in some degree - using an oxydator. They can also in some degree be adsorbed by active carbon

Sincerely Lasse

 

[Randy Holmes-Farley]

I agree the yellowness can be removed by oxidation, but the organic is generally not removed, just made less yellow.

 

[taricha]

I agree the yellowness can be removed by oxidation, but the organic is generally not removed, just made less yellow.

interesting distinction, as compared with GAC...

This - IMO - you can see by using ozone and in some degree - using an oxydator. They can also in some degree be adsorbed by active carbon

GAC actually does measurably remove DOC & yellowness etc quite well. I know people like GAC, but I still think it's underrated in the hobby.

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.

IMO - this the cause of "yellowing" of the water in a reef aquarium and it will be produced rather fast

There's two routes I can point to to create yellow DOM in the aquarium (a portion of this stuff is also fluorescent when hit with UV, if somebody not running GAC ever shines a UV flashlight through their tank and notices a blue-green glow.)

One you can just feed clear organic carbon and inorganic P & N.
the below was fed high NO3, PO4, and ethanol, aerate for a few days...


very yellow!
In this paper they did the same with feeding glucose to marine bacteria. Evaluation of the Production of Dissolved Organic Matter by Three Marine Bacterial Strains

The other way is degradation of photosynthetic pigments
Carotenoids are the likely precursor of a significant fraction of marine dissolved organic matter


So @Lasse did you do a Triton N-Doc during the no-water-change period?
(Thanks so much for providing tons of data.)

 

[Lasse]

did you do a Triton N-Doc during the no-water-change period

Only 12

Sincerely Lasse

 

[Lasse]

As I know it - the yellow substance is mostly humic acids.

Sincerely Lasse

 

[Lasse]

Here is my figures from the DOC test. By experiences - my NO3 concentration use to be around 60 % of total N

Sincerely Lasse