Refugium Refusal : Why would you NOT run a refugium?

[ReefGeezer]

I do not have a refugium. I have nothing against them, they were just not invented when I set up my tank. :cool:

Paul, your tank is a refugium!

 

[Freenow54]

I voted "No space, or equipment".

I don't run a sump to avoid the introduction of a siphon. Also, since I run a Peninsula-style tank, the one-tank-wall for HOBs has already gotten pretty busy with my HOB skimmer (Deltec MCE 601) and a DIY shelf for the Neptune Trident (perched above the water level to avoid a siphon). So I kinda have ran out of space.

Similar to some other posters, I kinda get the benefits of a fuge, but from seperately controlled systems. I run an ATS (SantaMonica Drop 1.6x), which keeps the nutrients in check (sorta) ... Nitrates at 0.03 ppm, Phosphates at 0.22 ppm (this needs work). I also seperately culture rotifers and copepods using culture kits from Reef Nutrition and Poseidon Reef Systems, respectively. My zoo plankton population is off-the-charts.

So, overall this assemblage has worked for me thus far, to help fill my fuge-sized-void. :p

I do not know if you can make one, but try to introduce a non siphon return. My tank has one. It simply fits into the return pipe on the base of your tank, and moves it to the top. My tank had one available to install. Works great

 

[hans4811]

Greybeard, this sounds absolutely ideal. Why do you think the hobby has gone away from this?

Hasn't here...!! Using a Triton style sump(>10% of DT), no socks, just a fuge full of Miracle mud, chaeto, Mangroves (found on beach), 2 types of Caulerpa, Gracilaria, Bristle/Spagetti worms, ministars, sea stars, more snails than you can count, pods galore...biodiversity abounds !! Love looking at it as much as I do my display tank! Everytime the fuge light comes on, I pop down and watch all the life scramble for its hiddy-hole....amazing !

And no real maintenance other than thinning out the growth every week or 2...no detritus really, some in the chaeto but the snails and pods usually keep it pretty clean !

 

[Iggy305]

I’m running a fuge, started with Sea Lettuce at first, great job exporting, but it’s a floater so it was always clogging the weir to the return section and messing with my ATO. Salinity was all over the place till I realized what was up. Dumped it in favor of Chaeto, but wasn’t really growing as expected. First batch died off, second batch suffocated by hair algae. This current batch seems to be thriving, granted I threw a lot more in this time, and switched to a cheap fuge light with a higher output and it seems to be taking off. Currently moving tanks but plan to add a little flow to it in the new build see if it helps keep it going.

 

[Borat]

Prefer my waterfall ATS and don't have the space for a good sized fuge.

I run waterfall ATS and a fuge. Sacrificed protein skimmer (never had one) - but never felt I needed one anyway..

 

[atoll]

I run waterfall ATS and a fuge. Sacrificed protein skimmer (never had one) - but never felt I needed one anyway..

I know from your Ultimate posts.

 

[monkeyCmonkeyDo]

I would say the only reason not to is space.
The fuge should be at least 1/3rd the volume of your dt. Not including sump volume.
If no room for it. No can do. A small one is still good for pods but theyve made artifical pod factorys now...
I guess you could make a seed fuge and transfer it and seed tanks with it... lol.
D

 

[monkeyCmonkeyDo]

Refugiums can vary just like ppls dt. Ive seen all algae fuges. All xenia. Ive done dsb. Diffrent sand grades. Rr. Small fist size rock buried. It was a.dark fuge for a long time. Big white sponge.
D

 

[galantra]

I truly wanted a Refugium to help keep phos, nitrate, and to keep ph from fluctuating. In the start I couldn’t keep any type of cheato alive. Even though I was having a high phosphate issue. I gave up a little even wanted to try other methods to help with export. Since then my system when through so many changes that either lead: hair algae issues, RTN for more than a handful of Sps, even almost nuking my tank with over dosing LC To drop phosphates. During all this I probably had just a strand of cheato that hung on and that bloomed to a massive amount. With that and all my tweaks it has added in keep my tank in line. I feed heavy and dose tons to help with sps and probably only perform a water change maybe every 3 or mor months of only 10% and all my parameters have been stable. I feel it aids in keeping everything stable

 

[Timfish]

I've messed with them. Now it depends on what is being kept in the refugium. If it weren't for cryptic sponges growing behind and around aquascaping in the DT I'd say cryptic sumps for them would be critical since they remove the labile hydrophilic and hydrophobic DOC much, much faster than the bacterioplankton in a system. A lighted 'fuge with corals would be beneficial as the DOC the corals release helps promote autotrophic microbial processes. But after reading the research showing how antagonistic macro algae for corals is and how the DOC it releases promotes oxygen reducing microbial processes as well as potentially promoting pathogenic shifts in coral holobionts not only would I never set one up for algae I'd argue they should never be recommended. For those interested in reading more start with Forest Rohwer'e "Coral Reefs in the Microbial Seas". And then here's a list of papers I've stumbled across over the years:

long-term stony coral survival in the Coral Reef Exhibit at Reef HQ Aquarium, Townsville, Australia using an ATS was measured in days, not years. (See figure 3 in the PDF attached)


Indirect effects of algae on coral: algae‐mediated, microbe‐induced coral mortality
Coral seperated from algae with a .02 µm filter die. Treatment with aampicillan prevents death.
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

Because sponges are essential players in the carbon, nitrogen and phosphorus cycle(s) on reefs here's some links to research done with them.

Element cycling on tropical coral reefs.
This is Jasper de Geoij's ground breaking research on reef sponges. (The introduction is in Dutch but the content is in English.)
https://www.rug.nl/research/portal/files/14555035/13completethesis.pdf
Sponge symbionts and the marine P cycle
https://www.pnas.org/content/112/14/4191
Phosphorus sequestration in the form of polyphosphate by microbial symbionts in marine sponges
(Chris Kenndall had a problem with low PO4 and had problems raising it with Neophos. Samples sent off showed phosphorus crystals developing in some of the sponges in his system accounting for at least some of his systems consumption.)
https://www.pnas.org/content/112/14/4381
Differential recycling of coral and algal dissolved organic matter via the sponge loop.
Sponges treat DOC from algae differently than DOC from corals
https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2435.12758
Surviving in a Marine Desert The Sponge Loop Retains Resources Within Coral Reefs
Dissolved organic carbon and nitrogen are quickly processed by sponges and released back into the reef food web in hours as carbon and nitrogen rich detritus.
https://www.researchgate.net/publication/279061640_2013_deGoeij_Science_Sponge_loop
Natural Diet of Coral-Excavating Sponges Consists Mainly of Dissolved Organic Carbon (DOC)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3934968/
The Role of Marine Sponges in Carbon and Nitrogen Cycles of COral Reefs and Nearshore Environments.
https://search.proquest.com/openvie...9d1e5/1?pq-origsite=gscholar&cbl=18750&diss=y
And since we're discussing favorable and not so favorable bacteria here's a paper looking at how different corals and polyps are influencing the bacteria in the water column.
Aura-biomes are present in the water layer above coral reef benthic macro-organisms
https://www.ncbi.nlm.nih.gov/pubmed/28828261

 

[RobMcC]

I don’t intentionally run a refugium on any of my tanks. I used to, and my most successful tanks had one. Reason is lack of space. I do run chaeto though (loads of people confusing algae scrubbing with a refugium in this thread: the rev described it well in the opener, but was widely ignored). Chaeto morning in a sump can approximate a refugium, but doesn’t provide as diverse a habitat as a refugium with sand /mud and rubble and a dark cryptic zone, which is what a refugium in the reefing sense truly is - it isn’t just or even primarily for nutrient control.

 

[blasterman]

I have to add phosphate and nitrate to my main tank. I dont even run a skimmer any more. SPS grows like nuts.

Why would I want to run competing macros?

I like cheato....but its a tool to solve a problem, and cheato requires lighting and care. I didn't get into this hobby to grow cheato. If you run high import and export cheato is a great part of the equation. I dont run high import and export.

Also, even if had a nitrate issue I've found a bag of biopellets in a sump nukes nitrate better than a skimmer or macro algae.

 

[nkyreef]

I like to keep my nitrates slightly elevated. When I've ran a fuge in the past it always works too well and removes too much nitrate. Hence I don't run one anymore.

 

[Bajie]

If you are building your refugium as a Refuge wanting to raise copepods to cater for Mandarin etc what is the advice regarding algae. I was going to focus mainly on chaeto to give the pods somewhere to reside along with siporax and a pod hotel [or two]
What about critters, is it worth having a snail or two and emerald crab to do some tidying up
I will have an X-Filter in the sump but this will be set to allow small pods through as they come through the return

 

[Lex_510]

I run a refugium, and I absolutely love it. Very easy to manage and one of the most effective filters IMO. All you need is a (decent) light and some algae and your'e good to go! Also saves you money and time, because you will need to do less to no waterchanges. You will need to dose te replenish minerals, but it's cheaper than salt.

New to a sump, What would you dose?

 

[MamaP]

I do run a refugium. I feel they are useful for newer tanks that are not mature enough to uptake all nutrients introduced into the system. My 125 gallon display has been up for almost a year and I have not had to clean algae out of the display tank ever. The refugium will get covered in all kinds of algae, but it takes maybe 10 minutes to clean out and maintain a month.

The refugium is just another type of filtration with added benefits. It's needs to be tuned and adjusted periodically. It's very easy to strip nitrate and phosphate out of the water column when running a refugium. However, they are a great home for microfana like copepods. It also helps buffer your PH at night if ran on a opposite schedule from your display lighting.

In the future when my corals mature into colonies I doubt i will need to rely on the refugium for nutrient control, however i will keep it around on a lower light schedule to keep the pod population up.

Question for you: I don't have a sump or refugium but am planning on having one on my next tank, but my question for you is how do you clean the algae out of your refugium in 10 mins?

 

[Lowlandreef]

New to a sump, What would you dose?

Depends on your tank and personal preference. In my case I don't do waterchanges so I will need to replenish the mineral uptake from the corals. If you do waterchanges you most likely won't have to dose anything, or maybe a little bit if the coral uptake is high. I personally dose All For Reef every few days.

 

[mmw64]

I tried having a refugium for a while but because it had to be in the same chamber as my skimmer the chaeto kept breaking off and clogging my skimmer pump. Cleaning my skimmer pump once a week, at least, convinced me to abandon the refugium.

 

[JayinToronto]

I've messed with them. Now it depends on what is being kept in the refugium. If it weren't for cryptic sponges growing behind and around aquascaping in the DT I'd say cryptic sumps for them would be critical since they remove the labile hydrophilic and hydrophobic DOC much, much faster than the bacterioplankton in a system. A lighted 'fuge with corals would be beneficial as the DOC the corals release helps promote autotrophic microbial processes. But after reading the research showing how antagonistic macro algae for corals is and how the DOC it releases promotes oxygen reducing microbial processes as well as potentially promoting pathogenic shifts in coral holobionts not only would I never set one up for algae I'd argue they should never be recommended. For those interested in reading more start with Forest Rohwer'e "Coral Reefs in the Microbial Seas". And then here's a list of papers I've stumbled across over the years:

long-term stony coral survival in the Coral Reef Exhibit at Reef HQ Aquarium, Townsville, Australia using an ATS was measured in days, not years. (See figure 3 in the PDF attached)


Indirect effects of algae on coral: algae‐mediated, microbe‐induced coral mortality
Coral seperated from algae with a .02 µm filter die. Treatment with aampicillan prevents death.
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

Because sponges are essential players in the carbon, nitrogen and phosphorus cycle(s) on reefs here's some links to research done with them.

Element cycling on tropical coral reefs.
This is Jasper de Geoij's ground breaking research on reef sponges. (The introduction is in Dutch but the content is in English.)
https://www.rug.nl/research/portal/files/14555035/13completethesis.pdf
Sponge symbionts and the marine P cycle
https://www.pnas.org/content/112/14/4191
Phosphorus sequestration in the form of polyphosphate by microbial symbionts in marine sponges
(Chris Kenndall had a problem with low PO4 and had problems raising it with Neophos. Samples sent off showed phosphorus crystals developing in some of the sponges in his system accounting for at least some of his systems consumption.)
https://www.pnas.org/content/112/14/4381
Differential recycling of coral and algal dissolved organic matter via the sponge loop.
Sponges treat DOC from algae differently than DOC from corals
https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/1365-2435.12758
Surviving in a Marine Desert The Sponge Loop Retains Resources Within Coral Reefs
Dissolved organic carbon and nitrogen are quickly processed by sponges and released back into the reef food web in hours as carbon and nitrogen rich detritus.
https://www.researchgate.net/publication/279061640_2013_deGoeij_Science_Sponge_loop
Natural Diet of Coral-Excavating Sponges Consists Mainly of Dissolved Organic Carbon (DOC)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3934968/
The Role of Marine Sponges in Carbon and Nitrogen Cycles of COral Reefs and Nearshore Environments.
https://search.proquest.com/openvie...9d1e5/1?pq-origsite=gscholar&cbl=18750&diss=y
And since we're discussing favorable and not so favorable bacteria here's a paper looking at how different corals and polyps are influencing the bacteria in the water column.
Aura-biomes are present in the water layer above coral reef benthic macro-organisms
https://www.ncbi.nlm.nih.gov/pubmed/28828261

Thanks. Great reads!
Wow, those studies really make one question the value of a Macroalgae refugium. From those studies it looks like we really should be creating stony coral with sponge refugiums!
The macro algaes are just such great primary producers and exporters of nitrates and phosphates. I don't think I could maintain my current fish feeding volumes without it. I used to think the algae exudate was basically doing my carbon dosing in my DT automatically and all the heterotrophic bacteria and other microorganisms it was feeding was a good thing! All of that discussion about the bacteria in the aura-biome or holobiont shifting towards the more pathological and reef unfriendly bacteria in the presence of algae exudate really makes me question what I'm doing. I wonder if the guys at AquaBiomics have seen a significant difference in tanks which grow macro-algae refugium vs ones that don't?

 

[vlangel]

I have run tanks with and without refugiums. The only reason I would not have a fuge is space. I would choose a fuge compartment before a skimmer compartment. I have found that a DSB and macro algae can be very effective at lowering nutrients. It also is a nice natural space for larvae shrimp and pods to reproduce and feed the tank. I like that balance.