Do you do water changes?

[StewL6]

I do small 5 to 10% water changes weekly (if I have to miss one I don’t sweat it). I dose All for Reef every day and a couple drops of iodide and a couple drops of Ferrion on Monday and Thursday. Started NP-Balance at .5 ml a day to see if it helps keep my phos and nitrate at my normal levels of .05 phos and 5 nitrates I don’t chase numbers but I chase stability. I am also excited I am going to submit my first ICP test this week after 13 months and the tank is looking great should be interesting.

 

[Greg Gdowski]

Water changes are the only way to get rid of the hydrophilic DOC that isn't removed by skimmers and GAC. Additionally, since corals and algae are promoting different types of microbial processes in the water through different forms of DOC they are releasing by redusing all the types of microbes in the water water changes allow have the potential of assisting corals in maintaing the microbial processes beneficial to them.

Here's links to some of the science:

Maintenance of Coral Reef Health (refferences at the end)


Aura-biomes are present in the water layer above coral reef benthic macro-organisms
https://www.ncbi.nlm.nih.gov/pubmed/28828261
Indirect effects of algae on coral: algae‐mediated, microbe‐induced coral mortality
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1461-0248.2006.00937.x
Influence of coral and algal exudates on microbially mediated reef metabolism.
Coral DOC improves oxygen (autotrophy), algae DOC reduces oxygen (heterotrophy).
https://peerj.com/articles/108/?utm_source=TrendMD&utm_campaign=PeerJ_TrendMD_0&utm_medium=TrendMD
Role of elevated organic carbon levels and microbial activity in coral mortality
http://www.int-res.com/articles/meps2006/314/m314p119.pdf
Effects of Coral Reef Benthic Primary Producers on Dissolved Organic Carbon and Microbial Activity
Algae releases significantly more DOC into the water than coral.
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0027973
Pathologies and mortality rates caused by organic carbon and nutrient stressors in three Caribbean coral species.
Starch and sugars (doc) caused coral death but not high nitrates, phosphates or ammonium.
http://www.int-res.com/articles/meps2005/294/m294p173.pdf
Visualization of oxygen distribution patterns caused by coral and algae
https://peerj.com/articles/106/
Biological oxygen demand optode analysis of coral reef-associated microbial communities exposed to algal exudates
Exposure to exudates derived from turf algae stimulated higher oxygen drawdown by the coral-associated bacteria.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3719127/
Microbial ecology: Algae feed a shift on coral reefs
https://www.nature.com/articles/nmicrobiol201661
Coral and macroalgal exudates vary in neutral sugar composition and differentially enrich reef bacterioplankton lineages.
https://www.ncbi.nlm.nih.gov/pubmed/23303369
Sugar enrichment provides evidence for a role of nitrogen fixation in coral bleaching
https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.13695
Elevated ammonium delays the impairment of the coral-dinoflagellate symbiosis during labile carbon pollution
(here's an argument for maintaining heavy fish loads if you're carbon dosing)
https://www.sciencedirect.com/science/article/pii/S0166445X19307192
Excess labile carbon promotes the expression of virulence factors in coral reef bacterioplankton
https://www.nature.com/articles/ismej2017142
Unseen players shape benthic competition on coral reefs.
https://www.ncbi.nlm.nih.gov/pubmed/22944243
Allelochemicals Produced by Brown Macroalgae of the Lobophora Genus Are Active against Coral Larvae and Associated Bacteria, Supporting Pathogenic Shifts to Vibrio Dominance.
https://www.ncbi.nlm.nih.gov/pubmed/27795310
Macroalgae decrease growth and alter microbial community structure of the reef-building coral, Porites astreoides.
https://www.ncbi.nlm.nih.gov/pubmed/22957055
Macroalgal extracts induce bacterial assemblage shifts and sublethal tissue stress in Caribbean corals.
https://www.ncbi.nlm.nih.gov/pubmed/23028648
Biophysical and physiological processes causing oxygen loss from coral reefs.
https://elifesciences.org/articles/49114.pdf
Global microbialization of coral reefs
DDAM Proven
https://www.nature.com/articles/nmicrobiol201642
Coral Reef Microorganisms in a Changing Climate, Fig 3
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7096749/figure/fig3/
Ecosystem Microbiology of Coral Reefs: Linking Genomic, Metabolomic, and Biogeochemical Dynamics from Animal Symbioses to Reefscape Processes
https://msystems.asm.org/content/msys/3/2/e00162-17.full.pdf

I found this interesting and distracting. In my classes that I teach, I call this dump and run. More specifically, dumping data without assimilating and conveying a message doesn't help. Indeed, the average person here is not a trained microbiologist and is not going to follow many of the articles that have been nicely cited from Pubmed. As a scientist myself, thanks for the effort.

Are there other things you end up removing when you change water? -- Of course there are. But none of us have ever said, do not change water -- ever. I will reiterate what others have said. All of us that dose, eventually will do a water change at some point in time to reset the system. There is no denying that dosing, and removing waste products through various means can successfully maintain a healthy tank for a long time without a water change. There is a lot of antidotal evidence out there from many reefers on these pages. If it wasn't possible, most of us would have pivoted when something didn't work -- and we would have told you on these pages. The question is not really whether one should do or not do water changes, but rather what is the interval of time between changes (days, weeks, or years).

I would rather see this thread change to -- how do we improve methods to lengthen the time between water changes even further.

I would suggest without direct evidence that the buildup of DOCs takes far longer than it takes to deplete alkalinity in a tank. That might explain why those of us that dose will eventually do a water change. Maybe that is what you were trying to say?

 

[Randy Holmes-Farley Verified Community Expert]

All of us that dose, eventually will do a water change at some point in time to reset the system. There is no denying that dosing, and removing waste products through various means can successfully maintain a healthy tank for a long time without a water change.

IMO, a much better question to ask than whether a tank "can" be maintained without water changes (as you note, the obvious answer to the question is yes), is whether any given tank might be improved (or not) by doing water changes.

The answer to the latter can only be determined by experiment, IMO, and the accumulation of organics is one of the reasons why it may be true.

 

[Jw258]

Gosh, I couldn’t imagine every 3 days honestly. Just for me at least. I know people do it all the time with picos especially. That’s an impressive feat to be able to keep good looking SPS in a pico so keep it up!

It was only 5l at a time so not a great deal of effort.

The biggest issue I had was the insane alk consumption which I couldn't manage with Kalkwasser because it was diluting my salinity in the volumes I was adding and also lighting. The UK distributor of Radions told me my glass was too thin to support the weight of an xr15 so I ended up upgrading the tank so that I could upgrade the light. My current tank is basically a big pico really. I only have a tunze 9004 skimmer and HOB. No reactors, rollers, socks, fuse etc.

 

[Greg Gdowski]

IMO, a much better question to ask than whether a tank "can" be maintained without water changes (as you note, the obvious answer to the question is yes), is whether any given tank might be improved (or not) by doing water changes.

The answer to the latter can only be determined by experiment, IMO, and the accumulation of organics is one of the reasons why it may be true.

Totally agree. But I think we would also agree that "dosing" was an experiment that has proven effective. As with all science, we need to move on to the next question that makes things even better (and hopefully easier for the hobbyist).

 

[Tidal Gardens Verified Sponsor]

We do water changes every week!

 

[Barnabie Mejia]

I am currently doing AWC of 3/4 gallon a day on my 75g/20L sump system. and I am dosing AFR, that is the only thing that gets dosed in it.

I think I may be needing to do more of a daily change because I get this hard algae on the glass that the glass scraper wont take off, I have to get in there with a razor blade to take it off. my nutrients are showing zero all the time and I cant seem to get them up. a while back I started to dose nitrates in very small amounts to the tank to try and help the coral, but it caused a little algae bloom on the rocks so I stopped it.

do you all think larger daily water changes would help it out a little?

 

[Ocean’s Piece]

We do water changes every week!

Hey Tidal Gardens! Glad to see y'all here!

 

[Dan_P]

how do you replenish the lost saltwater? i was thinking of doing it like that. I have an ATO but just for rodi

Good question!

I have automated nothing making this easy. The skimmate is replaced with an equal volume of new saltwater and then RODI is added to bring up sump level as needed. In the interest of transparency, I keep fish, Mexican turbo snails and soft coral.

 

[Greg Gdowski]

Good question!

I have automated nothing making this easy. The skimmate is replaced with an equal volume of new saltwater and then RODI is added to bring up sump level as needed. In the interest of transparency, I keep fish, Mexican turbo snails and soft coral.

I'd like to do that but have never figured out how to volume match what is coming out of the skimmer. How do you do that?

 

[Barnabie Mejia]

I'd like to do that but have never figured out how to volume match what is coming out of the skimmer. How do you do that?

I never know how much is coming out of mine on a regular basis... but I guess I could just measure the about of water it takes to fill the cup to trigger the overflow safety sensor and when the sensor is triggered, I could add that amount to it.

to be honest, I never thought about replacing the water that comes from the skimmer cup....

 

[Greg Gdowski]

I never know how much is coming out of mine on a regular basis... but I guess I could just measure the about of water it takes to fill the cup to trigger the overflow safety sensor and when the sensor is triggered, I could add that amount to it.

to be honest, I never thought about replacing the water that comes from the skimmer cup....

I've thought about it but never came up with a full proof way of doing it without messing with the salinity. As it is, I have to watch salinity as I skim to make sure I can add in the right amount of salt. My skimmer works well, but it is still highly variable --- sometimes draining a lot of water and in other cases not so much.

This is definitely a nice thing to have.

I thought about draining the skimate into a plastic bag within a reservoir of saltwater -- and then draining the saltwater back into the tank with an overflow on the reservoir.... (ie the bag of dirty skimate would displace good water back into the tank). I never tried it --- but I've thought about it ;-)

 

[Dan_P]

I'd like to do that but have never figured out how to volume match what is coming out of the skimmer. How do you do that?

I do everything batch-wise. I collect 24 hours of skimmate and then replace it. After replacing the saltwater, I can judge the amount of fresh water to add to replace what evaporated. I have not given much thought to performing this continuously or automating saltwater replacement. I imagine It is doable.

 

[Greg Gdowski]

I do everything batch-wise. I collect 24 hours of skimmate and then replace it. After replacing the saltwater, I can judge the amount of fresh water to add to replace what evaporated. I have not given much thought to performing this continuously or automating saltwater replacement. I imagine It is doable.

We have to get you on an automation schedule! ;-).

 

[smallcrpt]

I am currently doing AWC of 3/4 gallon a day on my 75g/20L sump system. and I am dosing AFR, that is the only thing that gets dosed in it.

I think I may be needing to do more of a daily change because I get this hard algae on the glass that the glass scraper wont take off, I have to get in there with a razor blade to take it off. my nutrients are showing zero all the time and I cant seem to get them up. a while back I started to dose nitrates in very small amounts to the tank to try and help the coral, but it caused a little algae bloom on the rocks so I stopped it.

do you all think larger daily water changes would help it out a little?

How is your AWC setup?
I've got basically the same setup. oh and i have the hard algae on my biocube, really fun the in the rounded corners!

 

[Barnabie Mejia]

How is your AWC setup?
I've got basically the same setup. oh and i have the hard algae on my biocube, really fun the in the rounded corners!

I built my AWC to run off my Hyros, and the pumps will move about 450ml/ min. the pumps will run for 1 min/ 7 times a day for a total of 3150ml. every 3.5hrs they will turn on. I finally have it down to where I have it send a notification to let me know there is 3 gallons left in the holding tank so I can mix up some new water.

I just wonder if I were to be changing more daily if that would help with the hard algae. before I was doing 20 gallon water changes every 2 weeks and I didn't have the hard algae issue. I am wanting to go with a larger mixing tank so I can either go longer without mixing, or push more volume in the AWC. kinda stuck but not stressing it either.

 

[Nebunu]

Havent changed water in 1 year and a half. Stable tank, all good.

 

[RMS18]

Auto w/c here, no hassle. Best decision ever. It also really depends on the coral you plan to keep. Softies, Lps sure you can get away with little to no w/c. Try running a SPS dominant tank (not your basic stags) with a lot of fish and w/c become a lot more important.

 

[Ocean’s Piece]

Auto w/c here, no hassle. Best decision ever. It also really depends on the coral you plan to keep. Softies, Lps sure you can get away with little to no w/c. Try running a SPS dominant tank (not your basic stags) with a lot of fish and w/c become a lot more important.

I only plan to keep a few SPS, so that’s why I decided to go down the no water change/dosing route. This thread has made me consider AWCs as a better solution, but I want to experiment with dosing first. So far, I have had great success.

 

[Susan Edwards]

no water change with dosing at the moment. I have what I need to set up an awc. Right now my nutrients are good so no need, but as it is a newly upgraded system, the load isn't super high. I also have a manifold for quick changes when I need. I do clean the sump with a gravel vac into the filter sock.

If my numbers drop, and they occassionally drop, I'll try the skimmate back into the filter sock!

I dose alk/ca/mg along with RS Trace Colors, AB+, NOPOX and some others as needed