Challenge: Creating a natural reef eco-system

[Jimbo]

This thread was inspired by GW's post to the "live rock curing" thread.

Here's a real challenge for any salties out there with a spare 5 minutes on their hands. Is it possible to create and run a self contained mixed reef tank completely naturally without the need to add any chemicals or nutrients?

For the simplicity of this thread we will assume the tank is already established and all parameters are correct. The only thing that can be added to the tank is top up water.

You can use any number of tanks, pumps, powerheads, sumps, refugiums, plumbing, pipes, etc, as long as no chemical are added. The use of symbiotic plants and animals (fresh water, marine, mamals, etc) can be used to help with nutrient uptake and replacement, for example, macro algaes (chaeto), plants (mangroves) and clean up crews (snails, crabs, starfish, etc).

People can be as creative as they want to get nutrients and chemicals into and out of the tank as long as it is performed naturally and human intervention isn't required.

Ideally, the system should work as a closed environment where everything is in balance. This does not preclude the designers from connecting multiple different solutions togather to create the final closed system as long as once the system is setup, nothing is added or removed.

I will start you off with a way to feed the tank. A green water system drips into a rotifer tank, which in turn drips into a refugium that is used to house copepods. The combined green water, rotifers and copepods can feed various corals and fish. Tank water passed through a fine filter is fed back into the green water system.

[Greatwhite]

I have been doing this since I started in reefs 8 years ago. I haven't dosed anything, except one time I used something to kill off cyano.

For 2 years, I hadn't clowns in a 20g somewhere of sight. I had even forgotten to FEED to poor fish for days at a time.

Now, my 90 has been up and running after a move since August - and I haven't done a water change.  My water is auto topped off, and that is all.

I feed frozen brine/mysis/spirulina blend daily. The rest if the food comes from pods and naturally growing algae.

My goal is to have a self sustaining system.

I would not even think of attempting this with fancy corals. But soft stuff like Xenia thrives. My zoas look good too.

Next challenge!!!!

[Greatwhite]

I have a brine shrimp hatchery as well, but I stopped using it after a week because it is ugly. I guess I could set it up in my sump, but hadn't bothered.

[Jimbo]

What kind of corals do you have? How do you keep your calcium and magnesium levels up? Whenever my tank's calcium levels drop, it really show signs of distress.

Getting back to the challenge, how would you change your system so you don't have to manually feed the fish. The objective is to create a self sustaining system where everything remains in balance both biologically and chemically. The true test would be that the tank, both fish and corals will be thriving and anyone could take a sample of the water and the parameters would be perfect.

[Hookup]

Not possible.

[Jimbo]

I'm sure it is. You just need to think outside the box (or tank) 

[Hookup]

Maybe I don't understand.

Closed system other than:

Rule 1. I can only add top up water, and food.

Rule 2. I can remove anything as long as its a natural process (examples are cleanup crew and cheats, mangroves, similar)


Therefore, No corals as Ca will be of limited supply.  And cannot be added back due to rule 1. Same with ALK and mg


I cannot see how to get rid of nitrate and phosphate buildup from fish food being added.  Will cheato or mangroves consume the nitrates as well as phosphates? 

Any nitrate remover is a chemical, sulfur is reacting with water and therefore breakes rule 2.  Carbon and Phosban have to be replenished, and therfore is not a closed system.

So...  I think it's impossible. 

Good challenge.  I'm sure smarter ppl than me will see what I cannot see.

[Hookup]

Maybe an algae turf scrubber would balance the food input so you could keep fish.  I don't have any experience with them to say they would reduce nutrients to 0ppm. 

So maybe fish only with LR could be possible.

[Greatwhite]

I took the challenge simply as - run a healthy system that doesn't require dosing or any chemicals.

I have a healthy system that has never been dosed with anything, and I have never added chemicals to speed up any process that doesn't occur naturally.

Phosphates and Nitrates are removed by my chaeto and a phosban reactor.  I allow a small amount of the loose green algae to grow on occasion because pods LOVE that stuff and I want to keep them happy, because when they are happy - my fish are happy.

I have a skimmer to remove waste - and the rest happens naturally with the live rock and whatever critters are living in it.

I have a bucket of RO/DI water that tops up the tank.

As I indicated, I don't keep fancy corals.  I keep what would be considered "beginner" corals like Zoas, Xenia, and torches/etc.  I just added an encrusting flower pot (Goniopora) who is doing very well.

If the challenge was to keep a super sexy system like Hookup's alive without "constant monitoring and replenishment of minerals" -- well, that I'm not doing.  I don't think that is possible without a dedicated pipeline to the ocean to keep getting fresh ocean water.

There's a reason that I don't publicly tell people a whole lot of detail about my tank.  I consider my system experimental, as I am really going against 99% of the "guidelines" set down by my fishfathers in history.  I do consider my experiment successful, as I see my system as pretty self sustaining, and I'm setting up to abandon my experiment and get back to the "traditional" salt tank methods in the near future.

The point of my post in the curing live rock thread was more for about the point of not trying to speed up curing the rock chemically.  I have also heard of people trying to rush their intial cycle chemically - and that ended with disastrous results more often than not.  With salt water, you need to be patient and let things happen naturally at the start.  After things are balanced, then it's OK to maintain the balance with dosing calcium, magnesium, etc to keep things healthy.

I plan on taking my findings to another forum to open discussion there with other experienced salties. You're welcome to follow...

[Thunda]

I took the challenge simply as - run a healthy system that doesn't require dosing or any chemicals.


If the challenge was to keep a super sexy system like Hookup's alive without "constant monitoring and replenishment of minerals" -- well, that I'm not doing.  I don't think that is possible without a dedicated pipeline to the ocean to keep getting fresh ocean water.

I think you hit the nail on the head though with this statement alone.  In the first post it says ...

"You can use any number of tanks, pumps, powerheads, sumps, refugiums, plumbing, pipes, etc, as long as no chemical are added. The use of symbiotic plants and animals (fresh water, marine, mamals, etc) can be used to help with nutrient uptake and replacement, for example, macro algaes (chaeto), plants (mangroves) and clean up crews (snails, crabs, starfish, etc)."

So the simple way to complete this challenge would be to take advantage of the plumbing, pipes pumps and run a line to a saltwater body of water and plumb it onto a set of tanks that you could then have set up to gradually replenish your tank with.  Use as top up waterHence always having fresh supply of all the necessary chemicals that corals/fish/inverts need... could plumb the output water back to the ocean as well in a return line.

Using the helpful start off by Jimbo "I will start you off with a way to feed the tank. A green water system drips into a rotifer tank, which in turn drips into a refugium that is used to house copepods. The combined green water, rotifers and copepods can feed various corals and fish. Tank water passed through a fine filter is fed back into the green water system."

have the tank stocked with live food fish such as Mandarin, scooters etc that feed off the little creatures on the live rock, general clean up crew we could have a system that would be would be more or less self sustaining... there was a article I read somewhere on line I believe it had been posted on ovas where the person was using pipes and reflectors to angle sunlight to the tank to be used as light for his tank...

This would be a basic start and could further be expanded on in greater detail but serves as a foundation ...

[Jimbo]

I think you hit the nail on the head though with this statement alone.  In the first post it says ...

So the simple way to complete this challenge would be to take advantage of the plumbing, pipes pumps and run a line to a saltwater body of water and plumb it onto a set of tanks that you could then have set up to gradually replenish your tank with.  Use as top up waterHence always having fresh supply of all the necessary chemicals that corals/fish/inverts need... could plumb the output water back to the ocean as well in a return line.
...
have the tank stocked with live food fish such as Mandarin, scooters etc that feed off the little creatures on the live rock, general clean up crew we could have a system that would be would be more or less self sustaining... there was a article I read somewhere on line I believe it had been posted on ovas where the person was using pipes and reflectors to angle sunlight to the tank to be used as light for his tank...

This would be a basic start and could further be expanded on in greater detail but serves as a foundation ...

Hi Thunda, GW,
You get the idea perfectly.

In terms of calcium and alk, all you need to do is find a natural solution where the by product is the mineral or chemical you want.

An excellent example of simple and effective filtration can be found at most water treatment centers. They use various granularities of substrate to filter the water, and then reverse the flow once every few hours to clean their filters. Plants can also be used to help with excess nutrient up take. I believe there is also an example of a water purification system that relies solely on fish, plants and the sun to produce potable water.

As this is theoretical, it doesn't have to be cost effective or have all the science correct, but the principle should be sound.

Hopefully, this will give some of us some ideas how we can improve our eco-systems.

[Greatwhite]

FYI...  The problem with topping up with sea water is that over time, your salinity will rise. Salt stays, water evaporates. That is why we top up with fresh ro/di.

I knew of a guy who moved to Hawaii and his water changes involved a walk to the beach with a couple 5g buckets.

[Thunda]

FYI...  The problem with topping up with sea water is that over time, your salinity will rise. Salt stays, water evaporates. That is why we top up with fresh ro/di.

I knew of a guy who moved to Hawaii and his water changes involved a walk to the beach with a couple 5g buckets.

Walk to the beach collect some more hermits/snails as well... would be nice...

so if we had a closed system complete with lid where water condensation would build up and fall back into the tank, or have a system that was totally water only with a stead flow in and out of fresh saltwater from a ocean...

[Hookup]

Tanks follow 2 simple rules:
1. Things get consumed and must be replaced
2. Things build up and must be removed.

Seems like the challenge is more about building a simple system that is healthy.   Not sure I understand the posted definition of closed system as closed system by nature means nothing in or out.

So the simplest system i can think of is 20% weekly water changes with very low bio load.  Simple, effective, and relatively cheap.  You can keep just about anything, depending upon lighting and flow, and all it takes is weekly maintenance.

[Feivel]

GREAT POST IDEA   

Well one natural way of producing calcium hydroxide include heating or burning pulverized oyster shells or bird egg shells, both high in calcium carbonate, and then adding the ashes to water to make a paste of calcium hydroxide.

Magnesium is also released from the dissolution of media within Calcium reactors. 

One could assume that this could be possible if you had a large size calcium reactor full of coral rubble wich will chemically turn themselves into what the system would need. So i would fill up a tank FULL of cured rubble and snail shells,and i would keep it in the dark to avoid algae growth and wich would inturn be a copepod dream home, The addition of Co2 could slightly bend the rules a bit, BUT still something that happens in nature, but to stay true to the question, i guess one could blow a lot of regular air with air pumps or venturri pump to help hasten the breakdown of the natural aragonite rocks, as they break down the theory would lie behind the built up trace elements are released back to the water and things like MG CAL and ALK are replenished. Thats why i would have a 75g tank full of this stuff and would change the flow to this tank to control the elements breaking down.

Algae control could be a combination of refugium, cheatos, macro algaes, DSB, Mangrooves, sponges,

Now other than the said mandarins and small predatory fish, to the possibility of some tangs, depending on how fast the macro algae grows, the food part would be the trickyist IMO.... but the green food rotifier copepod factory is a great idea.

Nutrience export, well the skimmer would essentially remove the fish oils and organic crud left behind that sticks to the bubbly froth. Cheatos and macros should consume nitrates, and in return the growth can be fed to herbivorous fish. yes you may have to physically remove algae from the sump and place them in the main display. kinda bending the rule a bit again unless it grows heavily in the main tank wich can be an eye sore.

@GW, You have luck with goniopora in that waterchangless tank, and i cant get the stuff to grow in my 10% weekly WC tank. you gotta be doing something right

But yeah to keep a ULNS tank for SPS and dose the "good stuff" like amino acids and overskim to remove the rest of the stuff to keep that prestine clear water they like, using bio pellets to strip everything else out of the tank, then to start running into problems and not knowing were to look. (wich is where i am now)

I love the timing on this thread, because i was looking into water changes and their effects and still trying to figure out a few things. So you dose this KALK, and add that MG do this test and that test, adjust everything, refine and tune it, now you have your stability you want, the daily dosing, everything goes great then BOOM Water change time, wel your tank water is now: 430cal, 9.8dkh and 1300MG, your water change water is: 380CAL, 6dkh and 1050MG .... see where this is going? This was my problem at one point, where when i did my WC my tank water DKH was 5.8 and the IO REEF W/C was 13dkh.... Yeah ...

Theoretically you could break down enough trace elements in the "calcium reactor" to maintain a sustainable coral load in the tank. Keep algaes and nitrates in check with refugiums, DSB, and other plant life that consumes these and returns other beneficial elements to the water chemistry. Skimmer would be working overtime, but thats ok. I still think the WC has a beneficial effect for nutrience export, im sure theres something we cant see or test for thats there that ONLY the WC can filter out.... but then again in nature they dont have a WC option.

Then again, All drains lead to the ocean

[Jimbo]

Excellent response Feivel, and all very true.

I agree with you that GW must be doing something right to have his level of success. 

How are the chemical and nutrients maintained in a reef in the oceans? Does anyone know how nature takes care of protein skimming, calcium, alk and trace element dosing, etc.

Personally, I believe that we are too focused on the tank and missing several key factors in keeping a healthy tank. We add sumps and fuges, but maybe we need to add dry tanks with other organics life to the eco-system to feed our tanks. I'm not suggesting going crazy here, but if you could capture the evaporated water and waster from our reef tanks, and feed it back to a dry tank, with the correct plants and animals, they could in theory meet the needs of your reef tank.

[Jimbo]

Theoretically you could break down enough trace elements in the "calcium reactor" to maintain a sustainable coral load in the tank. Keep algaes and nitrates in check with refugiums, DSB, and other plant life that consumes these and returns other beneficial elements to the water chemistry.

So is there a way to create a natural calcium reactor in our tanks that is self replenishing?

Maybe a clam tank containing adult clams and some clam shells thrown in for good measure, and highly oxygenated water - although you run the risk of the clams taking up more calcium than they produce. - Next throw in a clean up crew of a few snails and hermit crabs to take care of the clams that are nearing the end of their lives.

My hermit crabs are helping me create an organic calcium reactor by eating my snails every so often 

[Greatwhite]

Our tiny tanks cannot compare to an ocean. The sheer volume of water in the ocean keeps it balanced.

Additionally, there is much more life in the ocean that we do not encourage in our tanks. I figure that for everything that poops in the ocean, there is something that cleans up after it.

Waves push whatever is left over up onto the beach and the sand filters it out and cleaner water returns to the ocean. Whatever solid waste is left decomposes into nutrient rich soil.

Maybe we should fill our overflows with sand and see what comes out the bottom.....

[Jimbo]

... Whatever solid waste is left decomposes into nutrient rich soil.

Maybe we should fill our overflows with sand and see what comes out the bottom.....

How about sticking a mangrove in there as well!

[Feivel]

So is there a way to create a natural calcium reactor in our tanks that is self replenishing?

Maybe a clam tank containing adult clams and some clam shells thrown in for good measure, and highly oxygenated water - although you run the risk of the clams taking up more calcium than they produce. - Next throw in a clean up crew of a few snails and hermit crabs to take care of the clams that are nearing the end of their lives.

I think you kinda missed my statement, Not using live clams, but dead clam shells, snail shells, coral rubble because its already small and more easily decomposable, One could assume that a 40g breeder tank filled to the rim and blacked out to minimize algae growth, with a given amount of flow. Controling the flow would determine how fast the rubble would dissintegrate. Im no scientist but there may be a reason they use Co2 instead of oxygen (o2) ... maybee the added Carbon element bonds with the coral rubble and helps deteriorate it faster and returning the stored trace elements it consumed during its growth back to the water column.  I have not really researched the calcium reactor, i just know of it and its Co2 use to break down the rubble to calcium and preasumed trace elements stored in its natural creation. To keep it "chemical free" one could assume the addition of an air pump with venturi input much like a skimmer could pump enough air containing co2 into the said tank. the amount of air pumped in could also effect the decomposition times.

Maybee a said dehumidifier could accumulate enough water for top off purposes.

And use of a sort of undergravel filtration where the water is being fed to the underside of a DSB having no choice to pass completely through the sand. have nassarus snails and sand sifting starfish to eat the detritus that would build-up. And a forest of mangroves and cheatos and other macros, a said 4'x8'x12" tank could be essential for the mass of water that would have to be filtred.  This would be a good copepod heaven that could be fed the said rotifiers and planktons etc that inturn would provide the essential amino acids naturally produced

About the skimmer, it is said that it removes as much good as it does bad:
(http://www.advancedaquarist.com/2010/2/aafeature)
In summary, the skimmer is pulling out a solid mixture of compounds that consist by weight of (approximately):

8% inorganic ions
26 % of CaCO3
7% of MgCO3
21% of biogenic opal (SiO2)
38% of organic material
1.5% of phosphate
1.3 % of ferric oxide

Judging by these stats (taken by the bottom of the research) It does remove bad stuff, but as you can see the good stuff pulled out also. Including essential Amino Acids, And i know of some people that do not run skimmers at all and have very succesfull reefs. Posts elsewhere say that to test if you are removing too many nutrience is to take some of the skimmate and feed your tank, if the polyps extend your over skimming, or something of the sort. 

Theres Still LOTS to learn at keeping reef aquaria And its sooo rewarding too when everything goes good.