My first skimmerless system

[hubble]

I just removed my skimmer from the sump for a cleaning and didn't put it back. I'm only running a ATS and two mesh filter socks. Its only been a week so far but everyhing looks fine.

 

[Subsea]

I am all about filter feeders which includes corals. Ken Felderman has done extensive research on bacteria in reef tanks while testing effects of carbon dosing in reef tanks. His peer reviewed conclusion was that skimmate was 99% bacteria biomass.

Also of importance is dissolved organic carbon, DOC:
Protein skimmers removed at best 35%
GAF removed 60%
Reef tank biological filter removed 75%

Instead of removing skimmate for nutrient export, I would prefer to make money with what I remove.

 

[Timfish]

A friend of mine found this and I thought I'd pass it along. Here's a link to a great video produced by the University of California of Forest Rohwer discussing how increased carbon availability from turf and folacious algae promote pathogens that kill corals:
https://www.youtube.com/watch?time_continue=1702&v=-R2BMEfQGjU

 

[taricha]

Thanks for that, Tim. I think I remember that talk title used for a paper or two that were equally great.
Related Q I've had kicking around in my head about skimmerless.
How does a skimmerless system handle the vast undetectable arsenal of organics created by tank inhabitants. See http://reefkeeping.com/issues/2003-12/eb/index.php for a short list.

Is it solely up to activated carbon, or are there natural processes that mitigate these in a tank? If so, what factors affect a tank being able to process this stuff?

 

[karimwassef]

great video but I got a completely different take:

1. Carbon additions caused deaths - that would imply that carbon dosing would be deadly.
2. Microbes are potential pathogens - not proven pathogens
3. Most microbes eat the coral mucus. Corals can also consume DOC.
4. Algae in direct proximity to the coral create a microbial mass that can hurt the coral. Distant algae (turf scrubber) doesn't cultivate the same mass proximity.
5. The microbes suffocate the coral... hypoxia.
6. Grazing fish on coral reefs are key to coral health by eating the adjacent algae.
7. Stressors increase pathogens. Clean stable water conditions (with carbon sequestration and reduced nutrients) reduce pathogens.

There is no question that algae and coral compete for space and energy. But turf scrubbers actively increase both organics and oxygen. Keep in mind that the way scrubbers work is by creating an algae friendly zone separate from the coral zone! The coral zone is heavily populated by algae eating fish that keep the corals clear of nuisance algae.

So the combination of scrubber aeration, photosynthesis, and algae eating fish is a formula that maximizes the benefits of the algae scrubbers for coral. This also aligns with real experience of thousands of scrubber users who confirm the benefits and the increased growth.

Are there potential risks? sure. Are there ways to limit it? sure... there are plenty of examples in this video for how that works in nature and we can replicate them. The most exciting of which are things like the low tide "cleanse", giant clams as scrubbers, etc... It also ties back to the cryptic zone sponges and other filter feeders.... add grazers and filter feeders to keep the system in balance.

Thanks for a great post!

 

[Timfish]

Thanks for that, Tim. I think I remember that talk title used for a paper or two that were equally great.
Related Q I've had kicking around in my head about skimmerless.
How does a skimmerless system handle the vast undetectable arsenal of organics created by tank inhabitants. See http://reefkeeping.com/issues/2003-12/eb/index.php for a short list.

Is it solely up to activated carbon, or are there natural processes that mitigate these in a tank? If so, what factors affect a tank being able to process this stuff?

Thank You!

To start with GFO I do use it but genreally very infrequent, there's a lot of stuff, like sugars, it won't remove. I am trying a cup of it continuously in my Rimelss w/ Remote Lighting system

That's a very short list. Estimates I've seen vary from 10,000s to 100,000s.

For reference, DOC can be crudely lumped into three catagories, Labile, Semi-labile and Refractory. The Labile is very quickly metabolized by microbial processes and on healthy . Semi-refractory is a small portion and is metabolized by some microbial processes. Refractory DOC on a healthy reef is roughly 2/3s of DOC and is not normally available to microbial processes on healthy reefs and has life expectencies of years to millennia. On reefs that have the natural controls for turf and folacious algae disrupted* the increase in labile DOC (sugars) from proliferating algae promotes microbial processes that are able to utilize the refractory DOC. Two additional notes on refractory DOC; it collects in the deep ocean and can represent as much as 98% of the DOC and on reefs completely taken over by algae it can completely disappear do to heterotrophic microbial processes.

Steve Tyree when he stopped using skimmers to grow his corals argued back in the mid 90s cryptic areas with their associated organisms, especially sponges were critical. De Goeij confirmed Steve in his thesis work showed sponges remove the labile portion of DOC in 30 minutes that would take weeks for bacterioplankton to remove. These sponges are doing several things. They remove DOC and convert it into nitrogen rich detritus that is but back in the food change in hours. By removing the labile portion of DOC they remove the food source microbes that can process refractory DOC need to do so. The are physically removing the bacterioplankton that would be able to utilize refractory DOC. And remember, the bacteria beneficial to corals live on the coral, they're not found in the water column.

A couple more points about corals and bacteria I think need to be considered when trying to understand how DOC is working in our captive reefs systems. First, there certainly are times when compounds released into the water by corals affects other corals, I have seen systems start to "slow down" or show symtoms typical of "old tank syndrome" improve when the dominate coral was thinned out, I now try not to have any single species represent more than 10% of the biomass in a system.

Second, and I'm going to get on my soapbox about the absurdity of using the terms "SPS" and "LPS" to connote husbandry, we have been ignoring the differences between different species and varieties, ie genotypes, and how they may mitigate some of the misconceptions and resultant practices that are in fact detrimental to reproduction and long term success. We have over the decades selected genotypes that are highly adaptable and have more robust immune systems, just looking at the Acropora genus we are only growing a fraction of the species and looking at some of the specifics it's absurd to think we can keep many of them in the same system as they live in very different environmental conditions. We have also certainly selected genotypes that have more robust immune systems. Research by Wright, et al, looked at 8 different genotypes of A. millipora and found some quickly died when exposed to pathogens and one imparticular was indifferent to their attempts to kill it.


*Over fishing or pollution or disease. An example is Martin Moe's research on the urchin die off in the Caribbean in 1983.

 

[Timfish]

great video but I got a completely different take:

1. Carbon additions caused deaths - that would imply that carbon dosing would be deadly.
Yup! Feldman, et al, pointed out in his look at TOC in our reef aquariums that some of the reccommendations are very close to levels Kline, et al, showed would kill corals. I've seen systems by local aquarists who used carbon dosing not have any grwoth for a year or more and even kill their corals. Another problem I've seen mentioned is corals browning when using carbon dosing and this has always been assumed to be zooxanthellae but if in fact it's caused by an increase in mellanine what we're potentially looking at is an immune response due to bacteria. I sadly have also seen corals bleached with carbon dosing by removing too much phosphate and starving the corals

2. Microbes are potential pathogens - not proven pathogens
No, the increase in microbes does include an increase in pathogenic species, Vibrio in particular is one genus frequently mentioned. In our aquaria we also have to take into consideration we have selected species that have a more cosmopolitan distribution meaining adaptable and genotypes that have more robust immune systems, see the link in the above post. From their introduction "Our results suggest that lesions appeared due to
changes in the coral pathobiome (multiple bacterial species associated with disease) and general health
deterioration after the biotic disturbance, rather than the direct activity of any specific pathogen".

3. Most microbes eat the coral mucus. Corals can also consume DOC.
If you look deeper into the research the DOC produced by corals helps clear the water by grabbing organism and quickly settling out of the water. DOC produced by algae stays in the water promoting increases in heterotrophic microbes that include species pathogenic to corals

4. Algae in direct proximity to the coral create a microbial mass that can hurt the coral. Distant algae (turf scrubber) doesn't cultivate the same mass proximity.
Distance is a factor, but concentration is a factor too. In our systems we can't measure concentration and assuming algae is not causing problems because it's not immediately next to a coral is just that an assumption. If algae is competing with corals for nitrogen and phosphate and it's promoting an increase in the coral pathobiome (multiple bacterial species associated with disease) I don't see it as a good thing.

5. The microbes suffocate the coral... hypoxia.
Yup.

6. Grazing fish on coral reefs are key to coral health by eating the adjacent algae.
Yup. And urchins, the problems in the Caribbean can be directly tied to the Urchin die off in 1983

7. Stressors increase pathogens. Clean stable water conditions (with carbon sequestration and reduced nutrients) reduce pathogens.
No, stressors increase a corals susceptability to pathogens, increasing the pathogens only makes problem worse. And what is healthy water conditions, not what is "clean"? Quoting Charles Delbeek "Though reefs are often catagorized as nutrient "deserts" the influx of nutrients in the form of particulates and plankton is quite high when the total volume of water passing over a reef is taken into consideration. Our crystal-clear aquaria do not come close to the nutrient loads that swirl around natural reefs. And so when we create low-nutrient water conditions, we still have to deal with the rest of a much more complex puzzle. Much like those who run their aquarium water temperature close to the thermal maximums of corals walk a narrow tight rope, I can't help but think that low-nutrient aquariums may be headed down a similar path." Charles Delbeck, Coral Nov/Dec 2010, pg 127


There is no question that algae and coral compete for space and energy. But turf scrubbers actively increase both organics and oxygen. Keep in mind that the way scrubbers work is by creating an algae friendly zone separate from the coral zone! The coral zone is heavily populated by algae eating fish that keep the corals clear of nuisance algae.

So the combination of scrubber aeration, photosynthesis, and algae eating fish is a formula that maximizes the benefits of the algae scrubbers for coral. This also aligns with real experience of thousands of scrubber users who confirm the benefits and the increased growth.

Sounds good. But Delbeek and Sprung pointed out in their first book that ATS had an unacceptable coral death. The Townsend Aquarium in Autrailia is a good example. For 16 year they had a 100% coral death measured in weeks to months. They had to fix their problem by removing their ATS, constant siphoning of algae from the aquascaping and going from 10% to a 60% water change a month. Not my idea of successful.

Are there potential risks? sure. Are there ways to limit it? sure... there are plenty of examples in this video for how that works in nature and we can replicate them. The most exciting of which are things like the low tide "cleanse", giant clams as scrubbers, etc... It also ties back to the cryptic zone sponges and other filter feeders.... add grazers and filter feeders to keep the system in balance.

Thanks for a great post!

 

[karimwassef]

Individual failures can have many causes... there are too many successful thriving reefs to generalize that ATS kills corals. It's like saying that someone died from the common cold so the cold is deadly to all. No. Maybe their immune system was already compromised and that set off a chain reaction, for example.

Algae, sponges, urchins, fish... all part of the diversity that kept my tank healthy and growing. Do algae help in generating some pathogens? Yes. Does it hurt more than the algae helps? This is where we disagree.

Nothing here refutes or explains the success of reefers growing coral with ATS. It just informs a little more of the complexity.

 

[taricha]

That's a very short list. Estimates I've seen vary from 10,000s to 100,000s.



Two additional notes on refractory DOC; it collects in the deep ocean and can represent as much as 98% of the DOC and on reefs completely taken over by algae it can completely disappear do to heterotrophic microbial processes.



Steve Tyree when he stopped using skimmers to grow his corals argued back in the mid 90s cryptic areas with their associated organisms, especially sponges were critical. De Goeij confirmed Steve in his thesis work showed sponges remove the labile portion of DOC in 30 minutes that would take weeks for bacterioplankton to remove. These sponges are doing several things. They remove DOC and convert it into nitrogen rich detritus that is but back in the food change in hours. By removing the labile portion of DOC they remove the food source microbes that can process refractory DOC need to do so. The are physically removing the bacterioplankton that would be able to utilize refractory DOC. And remember, the bacteria beneficial to corals live on the coral, they're not found in the water column.



First, there certainly are times when compounds released into the water by corals affects other corals, I have seen systems start to "slow down" or show symtoms typical of "old tank syndrome" improve when the dominate coral was thinned out, I now try not to have any single species represent more than 10% of the biomass in a system.

Awesome info. Ties together a lot of things I've been thinking about.
Sometimes my tank gets phases of great growth in stony corals, and sometimes it halts almost entirely. And everything I can test and observe is unchanged. It just makes me think of the unmeasurable organics and bacterial voodoo.

Thanks for another push to get me to finally plumb the 5gal bucket with rock that I've had sitting around ready to become a cryptic zone.

I've had nice populations of sponges in lit areas in my display, but a (now gone) plague of asterinas wiped out some and left others. I'm sure the ones they left alone had much more noxious chemicals than the ones they ate.
An actual protected dark cryptic zone would actually allow me to have a sponge population that wasn't being selected by predation and tolerance to light/UV.

 

[Scrubber_steve]

quote from Timfish -
"Delbeek and Sprung pointed out in their first book that ATS had an unacceptable coral death. The Townsend Aquarium in Autrailia is a good example. For 16 year they had a 100% coral death measured in weeks to months. They had to fix their problem by removing their ATS, constant siphoning of algae from the aquascaping and going from 10% to a 60% water change a month. Not my idea of successful."
===================================================================================================================================

OK, this is outrageous Timfish; despite me proving your above assertion false beyond any doubt, in the cryptic sponge and sea squirt thread, you continue to not only ignore those facts, but now exegerate even more to promote this imagined scenario as fact, and thus I am now more than suspicious of your intentions.

You have an ill-conceived theory that rejects the utilisation of algae scrubbers & algae refugiums in aquaria, based on an implausible extrapolation of the conditions of natural reefs, negatively affected by the over growth of algae, directly due to external forces, that you choose to apply to aquaria where levels of algae are controlled & maintained as a matter of function & necessity. Apparently your utterly incorrect theory, as to why the Algae Turf Farm was removed from the Townsville Aquarium, is the analogy you have relied on to back up your ill-conceived theory.

For others reading this thread, & Timfish's comments on the Algae Turf Farm, once used at Reef HQ in Townsville Australia, here, again, are the facts.


The Algae Turf Farm (ATF) was removed from the Coral Reef Exhibit at Townsville Aquarium – Reef HQ, Queensland, Australia, because the man hours needed to maintain the 70, two meter by one meter screens, and 70 notoriously troublesome dump buckets that made up the Farm, could not be justified by the fact the Algae Turf Farm only accounted for 0.5% of the total algae biomass within the system. Negative effects on water quality had nothing to do with the ATF being decommissioned.

The facility was closed to the public in 2002 for renovations. A significant shift occurred during this time in regards to how the Coral Reef Exhibit was maintained. These changes were carried out for both coral mortality issues and budget issues.

The before and after periods are referred to as –
The “Oceanic Water period” (pre-2002) Average corals survival rate was only 20% to 30%, and the “Estuarine Water period” (2002 to present) corals survival rate increased to 70% to 80% (possibly higher now).

The changes made to the systems maintenance that were noted as most critical to improving coral survival rates were –

1. The switch from using priori ultra-clean oceanic water, collected offshore by barge, to using ‘less pure’ estuarine water collected on the incoming tide from the Ross Creek to increase nutrients and provide an external source of plankton.

2. The removal of all internal mechanical filtration (three large sand filters). This improved overall tank health by avoiding ‘over stripping’ the water column of particulates and encouraging plankton production, greater food availability, and larval settlement, especially during spawning periods

3. Internal circulation was increased.

4. The use of calcium chloride to raise average calcium levels (~ 250 mg Ca2+.L-1, to 420 mg Ca2+.L-1)

The Algae Turf Farm (ATF) was also removed during this period, but not due to any negative effects it had on water quality. And to suggest it was is utterly ridiculous.
Why; because the ATF made up only 0.5% of the systems total algae biomass. YES, ZERO POINT FIVE PERCENT. Removing the ATF left behind 99.5% of the systems algae biomass.

Further; in two articles written by marine biologists from James Cook University, Townsville, Queensland, Australia, specifically regarding this system and its maintenance overhaul, it is stated “Most importantly, the Algae Turf Farms effects on CRE filtration were negligible, especially when compared to the CRE’s overall internal algal mass productivity."

Moreover; not only was there no assertion in either article by these marine biologists that the Algae Turf Farm contributed any negative effects on water quality, there was no mention of any intention to reduce the remaining algae biomass for water quality issues or any other issues.


https://www.burgerszoo.com/media/560570/chapter-26.pdf

https://www.burgerszoo.com/media/560502/chapter-9.pdf

Further; Ecological purification in the captive reef – natural approaches to water quality management Ashley Sharp Zoological Society of London

Algal nutrient management

Case studies

In a case study conducted within the large reef exhibit (2.8 million litres) at Reef HQ, Townsville, Australia, the total biomass of algae supported directly on the ATS screens was approximately 0.5 % of the total algal biomass within the system (Pecorelli et al., in press). Consequently when the ATS was taken offline, the ability of the mesocosm to process nitrite and nitrate was not significantly affected. Indeed orthophosphate levels were significantly lower after the removal of the ATS, suggesting that the rupturing of the algal cells during harvesting was causing orthophosphate to return to the system.

Nevertheless, the nutrient processing capabilities of algae within any exhibit will depend upon a multitude of factors such as grazing pressure and light levels, therefore the use of remote vessels such as the ATS screens and refugia remain extremely useful tools to optimize algal growth.

https://www.burgerszoo.com/media/560510/chapter-11.pdf


Lastly, something of further interest to this thread is the fact that the Townsville Aquarium, during the successful upgrade to it's systems maintenance since 2002, is the fact they added four, 3 meter tall protein skimmers to the system as well as two other large skimmers utilizing ozone.

 

[Scrubber_steve]

A friend of mine found this and I thought I'd pass it along. Here's a link to a great video produced by the University of California of Forest Rohwer discussing how increased carbon availability from turf and folacious algae promote pathogens that kill corals:
https://www.youtube.com/watch?time_continue=1702&v=-R2BMEfQGjU

Yes, this is an interesting video concerning external forces & how it can affect natural reefs, but it is completely beside the point when considering anything to do with hobiests reef tanks.

 

[Scrubber_steve]

Individual failures can have many causes... there are too many successful thriving reefs to generalize that ATS kills corals. It's like saying that someone died from the common cold so the cold is deadly to all. No. Maybe their immune system was already compromised and that set off a chain reaction, for example.

Algae, sponges, urchins, fish... all part of the diversity that kept my tank healthy and growing. Do algae help in generating some pathogens? Yes. Does it hurt more than the algae helps? This is where we disagree.

Nothing here refutes or explains the success of reefers growing coral with ATS. It just informs a little more of the complexity.

Karim; Ignore Timfish' assertions regarding the Townsville Aquarium Algae Turf farm. It is more than a complete fabrication.

 

[Timfish]

Here's a current video

https://youtu.be/9SxQqGs9ICs

 

[boxfishpooalot]

Very nice! Still loving it! 21 years old? Wow. I wanted to ask you if your tanks water has lots of skimmer bubbles at the surface or not? Im curious if i disconnected the skimmer would the surface bubbles reduce or increase. Also do you use unfiltered tap water or ro? Whats the tds of your tap water?

 

[NYCBOB]

very nice. the xenia is helping to keep nitrate at bay. i myself stop using skimmer the past 1 year ad only run carbon. i can keep everything except mushrooms.

 

[Timfish]

Very nice! Still loving it! 21 years old? Wow. I wanted to ask you if your tanks water has lots of skimmer bubbles at the surface or not? Im curious if i disconnected the skimmer would the surface bubbles reduce or increase. Also do you use unfiltered tap water or ro? Whats the tds of your tap water?

Thank you! I don't get surface bubbles and I've never seen any difference before or after removing skimmers when I've been called in to fix a system in my maintenance business. This system gets tapwater filtered by carbon. I also use RO/DI on some of my systems. This system is one that uses tap water just treated with dechlorinator:

90 Gallon Mixed Reefhttps://youtu.be/4t8IjelZwUk
https://youtu.be/4t8IjelZwUk

 

[Timfish]

very nice. . . . i can keep everything except mushrooms.

Thank You! Your problem with mushrooms "might be" lighting. Purple, Red and Green Pinwheel mushrooms I've had for decades have generrally been very picky about intensity when switched to LEDs. Green Watermelons on the other hand have not had an issue. Try finding out the spectrum and intensity your mushrooms grew under and matching it if practicable.

 

[tmnails]

To be honest I have been running my 75 skimmerless for about 4 months now due to a pump failure. Been meaning to replace it but I think it's been doing very well. Tons of growth in softies and sps and my lps are splitting as well. I can't 100% say it's because of the skimmer but it does seem odd it all happened around the same time

I've wondered this myself. If you have a heavy bioload, it's hard to get away from a skimmer, but if you have a cheeto ball or algae in your sump AND your display has a low bio load, I wonder if you could get away from a skimmer completely...

 

[vikinglord13]

Many reefers have not had issues.

 

[almees]

I was doing a search on cryptic zones and found this thread, It was a very enjoyable read, with so much information and sources to reference.

I have a 180 gallon skimmer less tank with a 55 gallon refugium. Started as a 125 gallon about 12 years ago, moved houses once and about 6 years ago and then upgraded to a 180 because the center brace broke on my 125 1 1/2 years ago. I also have no algae issues with my tank and great growth from all types of corals.