Discus tank with no WC?!!

[Hans Kloss]

Of course it's impossible. But defeating Red Army is also impossible. Illiterates afghan warriors don't knew about it and because of it they finally won their battle against soviets. About 5 years ago I decided to be an aquaristic mujaheddin.
I live in the city placed by the river together with almost 1 million of inhabitants . About 1 million of people are producing unbelievable amount of...wastes. All these wastes are roughly neutralized in sewage plant and put into the river. Leaving my city this river shouldn't be named a river, but 5 miles down it becomes to be river again. Again low nitrates, plenty of fish etc. A miracle? No, it is self-purification process. Can we reproduce this process in our tanks?
Briefly there are two major components of water self-purification: oxidation of organic wastes to CO2&nitrate ions and de-nitrification of nitrate ions to nitrogen.
First of them is performed by bacteria in aerobic conditions using oxygen dissolved in water. Second one can be performed by another kind of bacteria using carbon-containing compounds in low-oxygen (anaerobic) conditions. Oxidation is going on during rapid flow of aerated water through pebbles, gravel etc. For de-nitrification low water flow through mud and tiny sand is necessary. Lets try to build self-purificated tank.

[Hans Kloss]

All measurement in meters/centimeters/milimeters.
On the bottom of tank 200x70x60(height) a glass box 100x50x12.5(height) was glued using silicon glue. Bottom of the box was coated using waterproof microporous coat on pvc grid placed 1 cm above tank bottom in identical manner like undergravel filter was made. 30 m of polyethylene hose (diameter 7 mm) was connected with one end inside plenum box under the coat.

[Hans Kloss]

Rest of the tank bottom was used for drain system, made with pvc pipes coated with waterproof coat on pvc grid. It is most important part of my undergravel filtration. All leakages were glued with silicon glue, hose was wrapped around plenum box.

[Hans Kloss]

Plenum box was filled with quartz sand 0.1-0.5 mm, the rest of the bottom was filled with basalt gravel 1-3 mm.

[Hans Kloss]

Undergravel drain system and plenum hose were connected with pumping end of powerhead 2500l/h , aquarium was filled with tap water and warmed to 28C. 5 l of detritus from my previous tank was added and aquarium was preliminary cycled using ammonia. After one week some plants were introduced and water parameters was gradually changed to gH5, pH 5.5. After 2 weeks 6 discus were introduced with no undesired effects. Tank is working over one year with 13 adult discus, 5 clown loaches, 5 medium size plecos, freshwater shrimps, bunch of otos and rummynoses. Water change- 50% once monthly with NO3 level 20-25 ppm. Water flow through undergravel filter- about 700-1000l per hour using surface skimmer. Water flow through plenum- about 120l daily.

[Hans Kloss]

Advantages of Jaubert plenum/undergravel filtration:
-no WC are necessary (LOL)
- no external water circulation, no more flooding at home
- no impurities removing, tank is almost fully self-cleaning

Disadvantages:
- gravel surface is coated with rhodophyta algae; it is inevitable problem of pumping undergravel filtration
- water conditions (pH, hardness) should be be REALLY suitable for discus
- low but constant pH diminishing is observed. Daily pH measurements are welcome, weekly pH corrections are necessary
- water is not perfectly clear. Tiny suspension of organic matter must be constantly removed by additional mechanical filtration
- phosphates and microelements are vanishing quickly and must be supplemented for plants growth
- after 1 month of no WC plants are usually stopping their growth for unknown reason
- tannins cumulation when driftwood is used
- very long time of fully tank maturing. After one year it is still not aged enough.
Hans

[Dolphin Dip]

wow! that really is amazing!
that really is a brilliant set up. something you might even consider marketing....

[White Worm]

Just sounds like alot of work and supplies to end up with more problems for little gain. It takes me less than a minute to drop the hose in the tank and start the syphon out to the front yard. I vac the bottom for a couple minutes (BB tank) then watch TV while it drains. Drop fill hose in tank, pour in prime, hook up to sink which takes 3 minutes tops. Watch tv while tank fills. So, wc takes about 10 minutes or less of actual labor. I do it once a week. I like clear water, no algae and dont have to worry about pH adjustments. I am only doing 3 more wc's a month without all the hastle and I also believe in over-filtration. Whats wrong with wc's?

[Dolphin Dip]

i agree with you miskus but think about it... if his plans could improved on some.. how many rich doctors wouldn't want a tank like that?

[crazie.eddie]

I belong to a plant forum and I know one of the members keep a heavily planted tank with discus and rarely performs a WC.

[Hans Kloss]

Whats wrong with wc's?

Try to leave your home for 4-5 weeks. I'm doing it yearly with no fear. Can you?
Hans

[OriTeper]

Advantages of Jaubert

Disadvantages:

- water conditions (pH, hardness) should be be REALLY suitable for discus


looks more like an advantage to me (or im not reading this right)

[pete321]

In the river that you mentioned, you said that the nitrates had returned to normal. One of the reasons for this is sunlight. Often underestimated in its importance of removing nitrates. Algae uses up the nitrates in the water like nothing else. I have been to commercial food fish farms that are overstocked recirculation systems with a 5 % weekly water change. This is only just a bit more that the water lost through evaporation. The filters comprise first of a settlement tank to settle the suspended solids and then a large open outdoor area of gravel and stone for biological filtration. The water is fed from the bottom and is aerated. The water on the top is green from algae. This last step is the nitrate control.

[tcyiu]

Hans,
I love the fact that you're doing this and stirring up some discussion. :thumbsup:

I hope you don't mind if I have a few questions re: your setup since I am not up to data on the therory behind self sustaining tanks.

1. What is the purpose of the the various bits and pieces of unconnected PVC lying on the bottom? Are they to provide voids within the basalt gravel? If so, what is the biological purpose?

2. Perhaps I am misinterpreting the pictures, but are the PVC pipes that form a rectangular grid, the water movement system for the UGF? If so, am I correct in thinking that water movement through the gravel is concentrated near the pipes? (Versus in off-the-shelf UGF plates where the movement is spread across the entire plate). And if this is correct, what is the theory behind concentrating water movement through the gravel?

3. The tubing wrapped around the plenum box is for removing nitrates, correct? What system is used to govern the movement to adjust speed?

4. Again, with respect to the tubing: What is the design principle behind coiling it around the plenum (versus laying it flat at the bottom of the plenum or for that matter the tank)?

Thanks again for sharing your design (and results).

Tim

[brewmaster15]

Hi Hans,
It'll be interesting following along this thread but I have some questions for you..

Can you elaborate on what you feed these fish and how often? I also noticed that you chose young adult to adult discus... have any bred in that tank ? Also have you tried to raise small juvenile discus to Adult or were the fish added as larger specimens. Do you think this system of yours will work as well as bare bottom tanks and water changes to Grow out fry?

You also mentioned that your nitrates are at 25PPM ? I'm confused on that... would you not have expected the combination of plants and plenum to keep the Nitrates at 0ppm... why do you think that its always around 25PPM when you do your monthly water change..


Thank you,
al

[White Worm]

Try to leave your home for 4-5 weeks. I'm doing it yearly with no fear. Can you?
Hans

I could not. :)

Still, If you leave for 4-5 weeks, would you not have issues also when you returned? Algae everywhere, a tank that is full of suspended organic matter from waste and food and how can you do your weekly pH adjustments that are neccessary?
You obviously do this on a much larger scale than I do and if you work out a tank with no w/c's that can be kept as clean as a BB / highly filtered tank, that would be great! Still seems like alot of work for the hobbyist. It may work better for the large breeder. Only problem is the majority are probably small hobbyists.

[Hans Kloss]

1. What is the purpose of the the various bits and pieces of unconnected PVC lying on the bottom? Are they to provide voids within the basalt gravel? If so, what is the biological purpose?

Exactly as you wrote. These shapes are for construction fastening only. They prevent coated pvc grid to crash due to the gravel weight. Empty space between bottom tank glass and gravel was made only for hydrodynamic reasons. It should assure equal water pressure in every place of bottom surface.


2. [...] are the PVC pipes that form a rectangular grid, the water movement system for the UGF? If so, am I correct in thinking that water movement through the gravel is concentrated near the pipes?
Yes they are. Their second purpose is to support coated grid.
There is a 5mm hole in each "short" arm of pipes grid to provide regular water supply for each small square between pipes. In case of accidental blocking (by pebble, snail shell, whatever) there should be still enough holes for proper water flow.


3. The tubing wrapped around the plenum box is for removing nitrates, correct? What system is used to govern the movement to adjust speed?

No, this tubing is too short for full denitration. It is only for preliminary elimination of oxygen dissolved in water. Denitration is going on in sand bed, but beneficial bacteria are very sensitive for oxygen and must be protected for all cost. Unfortunately they are slow-growing and easy to kill. Water flow is adjusted by little valve on the beginning of this tubing.


4. Again, with respect to the tubing: What is the design principle behind coiling it around the plenum (versus laying it flat at the bottom of the plenum or for that matter the tank)?

Tubing must be protected from bending or flattening because it is the only water supply for plenum. I've placed it as handy as I can for convenient removing in case of disaster e.g irremovable blocking or perforation. I know, it is impossible but ....
Hans

PS. In all my aquaristic life I've seen enough spectacular disasters to be extremely careful. I've seen major flooding caused by single snail, perforated coated hose which cannot be perforate, massive fish death due to one slipped tubing etc. Probably great part of my construction is not necessary or may be done in different, more simple manner. But I've tried to build as much bad luck-proof tank as I can. And as low-tech as possible.

[Hans Kloss]

Can you elaborate on what you feed these fish and how often?

I'm horribly overfeeding my fish. They are fed 4-5 times daily, twice with dry food and 2-3 times with salmon meat. For speeding up of tank maturing process only.


I also noticed that you chose young adult to adult discus... have any bred in that tank ?

No, these youngsters were introduced this summer shortly before my holidays. They are 1 year old


Also have you tried to raise small juvenile discus to Adult or were the fish added as larger specimens.

Only 2 of my fish were bought adult, 11 were raised from 3" kids.
Of course in bare bottom with 50% daily WC ;).


Do you think this system of yours will work as well as bare bottom tanks and water changes to Grow out fry?

I doubt of it but I'll try at the future.


You also mentioned that your nitrates are at 25PPM ? I'm confused on that... would you not have expected the combination of plants and plenum to keep the Nitrates at 0ppm

It will be major disaster for all system. I did it on the beginning and 0 nitrates caused my denitrification bacteria starving to death. Rebuilding of plenum bacterial flora takes me next 2 months. Never again.


why do you think that its always around 25PPM when you do your monthly water change..

It is NOT always 25 ppm. Shortly after 50% WC it is near 10. Then I notice 1 week of fast plants growth accompanied by fall of NO3 concentration below 5. During next 3 weeks nitrates rise slowly and stop near 25 ppm. Plants growth is also stopped at this point and ugly hairy green algae appear.
This tank is still far of balance and critical point seem to be WC ;(.
Hans

[Hans Kloss]

Still, If you leave for 4-5 weeks, would you not have issues also when you returned? Algae everywhere, a tank that is full of suspended organic matter from waste and food and how can you do your weekly pH adjustments that are neccessary?


Plants everywhere, almost no place to swim for fish. A lot of wastes and algae on plants leaves (cabomba, limnofila) but water reasonably clear. Very low nitrates, diminished shrimps population (great part was eaten by discus because of insufficient feeding from automated feeder). Reasonable pH (a little above 5) but shortly before my departure I did major WC with water of pH 6.5.
And most important- all fish alive and healthy.




You obviously do this on a much larger scale than I do and if you work out a tank with no w/c's that can be kept as clean as a BB / highly filtered tank, that would be great!

My tank is much higher filtered than any BB. There is constant filtration through 150 kg of tiny gravel and 50 kg of sand, it is not reachable by any external filter except of sump. My tank cannot be "clean" and never should be, because I don't want to keep discus only. I wish to possess a little part of living river bed with mud, algae, plants, fish, snails, shrimps and whatever can live inside.
It can give me much more fun than school of most beautiful discus inside of perfectly clean glass cage with tons of hi-tech devices.
Hans

[tcyiu]

.. hydrodynamic reasons.
I understand. Distribution across the under surface.

Along the lines of your disaster scenarios, could roots grow into this void and thereby clog it up.


..Tubing ... is the only water supply for plenum.
I missed that. I get it now. The tube is the intake for the plenum.

Thanks for the replies. GOOD LUCK!!

Tim

[Hans Kloss]

Along the lines of your disaster scenarios, could roots grow into this void and thereby clog it up.


Yes, they can but it cannot stop water flow. Last year I dismounted similar UGF in my R.I.P old tank and have been found some plants roots inside. All these roots were perfectly clean but away from water intakes, probably they don't like rapid water flow. Btw. I've tried to find some detritus for my new tank hoping this void can collect it. No way, there was maybe a quarter of glass of muddy water in 110 gal tank after 3 years of functioning with no cleaning.
Hans

[jczz1232]

Very nice built, never seen a tank like yours. Have you loss any fish with this setup yet? It might be your lighting or something but some of your discus are darken.

John

[architect1]

Wow thats crazy, one thing I notice is your discus are really dark looking, is that the strain, new to the tank or what?

[Hans Kloss]

one thing I notice is your discus are really dark looking, is that the strain, new to the tank or what?

It is my ability of taking photos without flash ;). Of course those fish on the left were darker because they are swimming over the black bottom and in the dark corner. Those on the right over white sand were colored normally.


Have you loss any fish with this setup yet?

During last 3 years I've lost 1 discus in quarantine BB due to the gill infection caused by chilodonella protozoan. In this tank I lost about 20 rummynoses, which were slaughtered by my flat monsters.
Hans

[Apistomaster]

Hi Hans,
Your's is a design that relies on advanced understanding and application of the capabilities hypoxic denitrifying bacteria which are, as you have pointed, out narrow niche organisms. A great concept tank but not one the average discus keeper could pull off.
It is tricky to make this work well in a reef tank where the principles were first applied at some scale.
More of a tour de' force of your mastery of aquatic biology, which I mean as a compliment
That is, if I understand what you are demonstrating. Not something that would be easy or practical to scale up for a hatchery or reselling operation.

[Dennis The Mennis]

I love this setup. With the weather extremes we've had over the last few years, the word drought seems to be more and more present in our daily lives. Keeping Discus, or any aquatic environment with this type of tank may become increasingly popular if these extremes persist.

[Hans Kloss]

That is, if I understand what you are demonstrating. Not something that would be easy or practical to scale up for a hatchery or reselling operation.

Over 20 years ago I visited small hatchery established on denitrification idea. Each BB tank was equipped with external 5 gallon canister filled with tiny sand and primitive internal sponge filter, providing small (daily about 1/3 of tank capacity) water flow through canister denitrificator. Its owner found this way of discus keeping by himself, having quite horrible tap water (about 30gH, pH near 9). It was pre-RO era and each gallon of water for discus breeding was prepared using ion exchange resins which is expensive, time consuming and laborious method.
In case of discus were sold out the hatchery owner fed denitrifying bacteria with ammonium nitrate and sugar or vodka ;). He joked he is in fact bacteria breeder because all his fish can easily take care for itself, only bacteria cannot.
Btw. I didn't mention it previously but the presence of DOC (dissolved organic compounds) in water is essential for denitrification process. Bacteria use NO3 ion INSTEAD of oxygen to oxidize organic compounds to CO2. In case of no DOC are present in water bacteria are stopping to denitrify and starving.
Hans

[FishLover888]

Great set up Hans. You should perfect it and marketing it. I would love to buy one just to reduce the WCs.

Water is a very valueable resource and I do feel guilty dumping about 200g water each week for my fish. I only have a 125g tank and I think most of you will be going through much more water than I do for multiple tanks. If we can all cut down the amount of water we use, it will be a positive impact on a big scale to the whole fishkeepying hobby. I think that's very important.