Are water changes over rated?

[Troylee]

I've dug into Advanced Oxidative Process a bit more and have to disagree with it's use to eliminate water changes. A major portion of the DOC in a system is refractory meaning it's resistant to degredation. The problem with adding labile DOC to a system is it allows heterotrophic to utilize refractory DOC as food source and proliferate. You're correct AOP will break down both the DOC as well as any microbial stuff. But it doesn't seem to be s effective as you assert with this paper only achieving 50% reduction at the optimal dosing. (Did you actually test for DOC or TOC in yor experiments?) While the process does break down DOC into water, CO2 there are also BIODEGRADABLE molecules left in the water. If those biodegradable molecules are returned to the tank that's only going to promote additional microbial growth so i don't see how AOP can be considered as a viable alternative to water changes.

(Table 4 from this paper was interesting comparing the cost to remove 40% of teh DOC from RO effluent in wastewater treatment:


)

Have you read salems new article on reef builders about doc? He seems to be digging into it very deep and blaming it on the natural reefs disappearances. It’s a worthy read…

 

[GARRIGA]

Don’t recall if I’ve mentioned this here but in a question to Randy he replied that AOP converts ammonia to nitrate. Therefore a two edge sword that must be considered since corals prefer ammonia same as plants but at the same time should there be a death this would allow the conversion from more toxic to less extending the time available to solve the reason causing it and might be a viable option for QT where setting up biological quickly requires expensive bottled and refrigerated bacteria. Seems only remnant being nitrates which can easily be solved later. Could therefore substitute for a skimmer assuming I can confirm what it does to detritus and degree of surface residue which represents protein the skimmer would have removed. My understanding. Any feel free to correct me. Last I want is to carry misinformation or parrot it.

As with anything. My approach will be to apply it judiciously based on objective sought and why first will be conducting various tests to the level of expertise and understanding I poses. Nothing attempted is nothing gained.

Also. Member on another forum had been running this for pathogen control on their display tank since 2021 and seems to be having great success confirmed by DNA tests. Just started reading therefore can’t comment beyond that but at the moment no apparent side affects although as far as I’ve gotten don’t think they fully grasp how it actually works or what else they should be looking for. Might join that discussion although fear being new my post count will just get me ignored as well as lack of build or badges.

 

[dr_vinnie_boombatz]

Think it depends on the salt!

Was using Instant Ocean and water changes were a pain - had to let it run overnight, adjust the parameters; switched to Red Sea Blue and LOVE doing water changes. Don't have to adjust parameters, ready to go in 1 hour.

Also depends on your PO4 and NO3. Skipping a weekly water change if these fall too low in my books is okay. There should be a baseline % for a weekly water change, but this should change depending on your parameters.

I do a weekly 15% WC and dose AFR throughout the week.

 

[GARRIGA]

Have you read salems new article on reef builders about doc? He seems to be digging into it very deep and blaming it on the natural reefs disappearances. It’s a worthy read…

Speaking to what I understand to that article. Here in south Florida the taking of parrot fish has been deemed illegal because we understand they keep the reefs clean of algae. Not sure what’s happening in the Bahamas but as pointed out in the article overfishing of herbivores partially to blame. Confirmation CUC the most valuable aspect of algae control and not nutrient control to me.

Can’t speak about DOC as beyond my knowledge base other than rudimentary understanding yet article talks about oxidation via ozone which is what would occur when peroxide interacts with UV-C. Therefor seems to confirm my theory on its use and in my application the only organisms being affected would be those in the water passing the UV-C when peroxide in solution. Display and filtration would still contain a healthy microcosm and why perhaps periodic use more prudent then 24/7 sterilization.

Trying to validate with Randy if AOP crestes OPO as to determination if GAC then needed. From using peroxide alone my water was rather clear and absent GAC. Perhaps only occasional use if OPO not a concern.

Article further reinforcing my new found knowledge of sponges and oddly reason I’m testing an FX2 with a 20g being I’ve considered putting sponges in one of the trays but not certain if flow was going to be excessive. Perhaps based on the article that was an unfounded concern on my part. Again testing will reinforce or negate that idea.

I agree that past 25 year plus dogma not a reason to stay the coarse and why I’m always challenging old concepts although often find myself going back to the past as with upcoming build employing a plenum or what I prefer to just call an undergravel filter. However this will be in conjunction with other ways water is drawn as I doubt organisms will enjoy high flow pulling vertically but then that’s to be tested as well.

Here the article. Very good read. Thx for the heads up

DOC is The Most Important Parameter For A Healthy Reef Tank: Here’s a New Method to Manage It | Reef Builders | The Reef and Saltwater Aquarium Blog

In this article, I will provide an overview of my take on the current zeitgeist of reefing and explain why the entire industry is ignoring a critical aspect of coral care. I will explain what issues…

reefbuilders.com

 

[-XENOMORPH-]

To each his own. ...it's easier for me and cheaper for me (I don't dose)...to do a weekly 5 gallon w.c. ....that and my Skimmer collection... (yuck) and then they don't swim in pee.... hahahha.
The no w.c. thing..... I completely understand it. i really do...i just choose not to do it. To each his own

 

[Necrodaemus]

In my 100g system, I haven’t done a WC since December ‘23. The tank is a mixed reef, SPS dominant and is maintained by All For Reef and occasional dosing of potassium (AFR doesn’t replenish K elements), which I test for and keep at 400-420ppm. My nutrients stay around 1-5ppm NO3 and 0.05-0.07ppm PO4 by my skimmer and chaeto refugium. Once every 6-8 weeks, I run carbon just to help with any potential toxin buildup. For my system, this has been working perfectly.

 

[Timfish]

Yes, it's fascinating research on atmospheric processes and hyroxyl radicals. But making refractaory DOC biodegradable by microbes might "sound" like a good thing but the research, which I linked to earlier in this thread, clearly shows increasing microbial growth by adding increased labile DOC is bad for corals. Using ozone or UV to breakdown the refractory DOC into labile forms that can be biodegraded by microbial processes only accomplishes duplicating what Haas and others has shown is detrimental for corals.

 

[VintageReefer]

 

[VintageReefer]

Sooo…don’t use ozone or uv long term?

 

[VintageReefer]

I don’t do water changes
Phosphates currently .4-.5
Nitrates around 6-6.5

Everything is growing and looking fine, no algae issues in the tank either

 

[Randy Holmes-Farley]

Sooo…don’t use ozone or uv long term?

IMO, it’s a stretch to draw such a conclusion.

 

[VintageReefer]

IMO, it’s a stretch to draw such a conclusion.

I’m just trying to figure out what claim is being made in that post

 

[Randy Holmes-Farley]

I’m just trying to figure out what claim is being made in that post

I understand.

 

[GARRIGA]

Yes, it's fascinating research on atmospheric processes and hyroxyl radicals. But making refractaory DOC biodegradable by microbes might "sound" like a good thing but the research, which I linked to earlier in this thread, clearly shows increasing microbial growth by adding increased labile DOC is bad for corals. Using ozone or UV to breakdown the refractory DOC into labile forms that can be biodegraded by microbial processes only accomplishes duplicating what Haas and others has shown is detrimental for corals.

Is it possible that employing sponges would resolve the labile DOC remnants of hydroxyl radicals on DOC? Are there perhaps other remedies to solve this? Point being for every reaction there tends to be consequences and best solve latter vs just giving up on that path.

For example, veggie filters solve low pH by removing excess co2 yet consume iron needed by corals which we can later dose to compensate vs not using veggie filters.

Path to zero water changes might bring out ingenuity or might not but I find it more productive to keep seeking answers vs just giving up and returning to those dreaded buckets. Auto not pragmatic for my living space.

 

[Northern Flicker]

I am straight up too stupid to understand some of what is being proposed here. Best I can do is follow the guidance of people with successful tanks and hope they understand the science.

I love having all of these talented people on the cutting edge of our hobby, though.

 

[Aquariumaddictuk]

I waterchange around 15% a week.
I keep discus which have 2x 50% per week so I think it's just an inbuilt function.
My tank is ZEOVIT so also following the guidelines despite the fact testing lots of different parameters tells me it's probably not needed.
There's lots of elements in a domestic home e.g detergents, sanitizers, aftershaves etc etc that we can't test the passive, negative effects of so for me it just makes me feel a bit safer to do it

 

[apb03]

I waterchange around 15% a week.
I keep discus which have 2x 50% per week so I think it's just an inbuilt function.
My tank is ZEOVIT so also following the guidelines despite the fact testing lots of different parameters tells me it's probably not needed.
There's lots of elements in a domestic home e.g detergents, sanitizers, aftershaves etc etc that we can't test the passive, negative effects of so for me it just makes me feel a bit safer to do it

I totally agree with that perspective. What if you go to the bathroom five minutes before and wash your hands with soap? Or you just hopped out of the shower? Or did your significant other decide to light up a scented candle?

Many things can happen in the house that may be out of your control, which could inadvertently introduce toxicity to your tank.

It's simply not something I want to worry about. Skipping water changes can work, primarily if you focus on easy-to-keep corals, have a minimal number of fish, and are comfortable with dosing specific elements. You also should be vigilant about chemical use in the home and wear gloves at all times because you cannot afford pollutants to enter the tank.

If you are new to the hobby, please change your water. There are enough posts on the board as it is of failed reefs.

 

[Northern Flicker]

Ya I don't really know what the downside could be, even if the upsides are debated.

I mean even in ultra-low nutrient systems, you are likely dosing back up any lost nutrient concentration. Non factor.

I've never really seen a coral react poorly, only the opposite.

 

[SomeHappyFish]

What, therefore, would be the ideal or preferred method of exporting nitrate/phosphate in a system that remains operational by administering an alk solution, calcium and magnesium without performing a water change? For the purpose of perfecting this no-water-change technique and documenting it; I'm prepared to test it on my other tank as I haven't performed a WT since the beginning of July.

When I say no water change I exclude the added water that I added when adding fish, snails, corals or correcting the salinity.The water I added while adding fish, snails, corals, or adjusting the salinity is not included when I declare there has been no water change.

-Algae turf Scrubber

-Cheato reactor

-Macro Algae in the display

-Carbon Dosing

-Oversized Skimmer

Last time I test my Nitrate/Phosphate they were at 22.7 ppm and 0.021ppm

 

[GARRIGA]

What, therefore, would be the ideal or preferred method of exporting nitrate/phosphate in a system that remains operational by administering an alk solution, calcium and magnesium without performing a water change? For the purpose of perfecting this no-water-change technique and documenting it; I'm prepared to test it on my other tank as I haven't performed a WT since the beginning of July.

When I say no water change I exclude the added water that I added when adding fish, snails, corals or correcting the salinity.The water I added while adding fish, snails, corals, or adjusting the salinity is not included when I declare there has been no water change.

-Algae turf Scrubber

-Cheato reactor

-Macro Algae in the display

-Carbon Dosing

-Oversized Skimmer

Last time I test my Nitrate/Phosphate they were at 22.7 ppm and 0.021ppm

Done all recently minus the skimmer. Last skimmer was used was the 90s which is nothing more than a glorified mechanical filter requiring human action to remove that skimmed but does add aeration yet can't see where algae wouldn't easily solve that. Until I tested new lights with doubling light intensity and longer duration tank was humming on just carbon dosing which I later stopped and seemed denitrification finally matured as I no longer had algae issues in the display although kept same overfeeding schedule. No corals as I was testing decomposition. Yet as it pertains to that affected by food. All good. No WC for 2 and half plus years.

Absent the water changes, one stops throwing nitrates out with the bath water and allows it to replace alkalinity lost during nitrification. My alkalinity stayed at 9 and all I ended up testing as change in that which let me know nitrates bottomed out or excessive. Thinking now that since alkalinity not being consumed by throwing it out then replacement should be only that corals use. Have to believe dosing going to be easier yet haven't tested that but will soon as test tank back up an running. I procrastinate.

Ignoring the assumption coral warfare may persist or hydroxyl might create detrimental DOC there's the fact tank will be more stable as less chance of any element including salinity going off because replacement water wasn't set same as display. Can't imagine dosing being more complicated since now it should be purely based on consumption and change coming from growth which not expected to be so accelerated that weekly testing won't keep it dialed in. Absent new additions. Gotta believe past initial setup this becomes set and almost forget minus the periodic ICP to ensure elements consumed as assumed and increased for additional growth or new additions. Science indicates all elements don't have to be present at all times in exact ratios therefore there's buffer to get trace dialed in and simple enough to periodically test major elements and ensure those are on track.

Only one way to find out. Stop throwing water out. Doubt tanks are going to suddenly crash.