# Anybody running without filters?



## bikinibottom (Nov 18, 2012)

Back in the day I ran my saltwater tanks with no filters. And I did a 25% water change maybe once every 3-4 months. And I never had a fish loss or coral loss until I lost power for a week straight during the derecho.


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## Rich Guano (Jan 19, 2012)

Your a brave soul. From what I read about salt tanks, proper filtration is the biggest push. Sorry to hear about the power outage messing up your tanks. What problem put an end to you run? Loss of lighting?


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## funkman262 (Nov 11, 2010)

I only used a filter until my plants were able to keep up with the bioload on their own. I had a heavily planted tank with no filter, no water changes, nutrient dosing, and CO2 running for nearly 2 years (would still be running like that now but had to restart when I moved for a year and left the gf in charge of running the tank...).


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## manzpants92 (Dec 6, 2012)

interesting thread. I too just read the ecology of the planted aquarium and the idea is pretty crazy but it all makes sense. I'm planing on doing a small set up and was thinking about not running a filter


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## Rich Guano (Jan 19, 2012)

@funkman Way to go! Thats what I talking about.

I have a 38G that has been running continuously since 2004. I have always used Marineland BioWheel Filters on this tank. Prior to having plants (added Feb 2011) The BioWheels always had a thick layer of bacteria growing on them. After the plants became established, the biowheels became void of bacteria, and since have been removed.

I would like to ween the tank off the filters entirely and reduce them to simple power heads moving water around internally.

I recently read that a engineer knows his work is finished not because anything else can be added to the design, but that nothing else can be removed. Its simplicity that I seek.


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## Dtitus1 (Jan 20, 2013)

Idk, I still wouldn't do it, the reason saltwater works without a filter (I still run one in mine regardless) is because your live rock builds up bacteria colonies that break down the waste.

Your plants aren't going to break down waste into usable nutrients, they're just going to use them, but if there's nothing to grow bacteria on to break down the waste it's just gonna build up and look nasty.

Now there should be some bacteria in your substrate, but this isn't really an efficient place for them to colonize in large numbers, so it would work to have no filter if you had incredibly low stocking in livestock, but still I'd just have a filter and more fish.


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## Dtitus1 (Jan 20, 2013)

Just thought about it, you could get dry rock and use freshwater live rock with the powerhead, same theory as saltwater. Wonder if anyone has ever done that....


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## Diana (Jan 14, 2010)

I have run plant only tanks with just a power head. (often Koralia style)
My tanks that are infested with fish, though, all have filters of some sort. At least a sponge over the intake of the power head. (traditional style PH with a place for a sponge).


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## funkman262 (Nov 11, 2010)

Dtitus1 said:


> Your plants aren't going to break down waste into usable nutrients, they're just going to use them, but if there's nothing to grow bacteria on to break down the waste it's just gonna build up and look nasty.


A little confused here. Why would breaking down the waste via bacteria be better than the plants actually consuming the organics? Plants are much more efficient at nutrient and waste removal than bacteria is, which is why more research is being put into constructing wastelands or algae ponds for the use in wastewater treatment in which bacteria removal is currently the conventional method. Certain species like duckweed varieties especially are being researched for their ability to remove heavy metals.


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## bikinibottom (Nov 18, 2012)

Rich Guano said:


> Your a brave soul. From what I read about salt tanks, proper filtration is the biggest push. Sorry to hear about the power outage messing up your tanks. What problem put an end to you run? Loss of lighting?


Combination of things. One major stress was the temperature -- it was like 104 degrees after the storms, and the corals have a pretty narrow thermal range. Fish didn't like it either. Probably the next biggest stress was no water movement, meaning low oxygen. More of a problem for the fish, but corals do rely on water movement so that sediments don't settle on them and irritate them. No light -- corals depend on light for their nutrition. So everything combined was just too much.

One reason I was able to get away with no filtration is because I kept small tanks, less than 50 gallons. My filtration was totally biological -- lots of "live rock" and sand. The filter I currently run on my planted tank is just some sponges and the little ceramic rings -- yeah, I'm catching more of the fine debris and cleaning it out monthly, but really what you're doing is creating more surface area for bacteria -- biological filtration. You could achieve the same thing by creating more area in your tank to perform the same function.


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## funkman262 (Nov 11, 2010)

Since we're also discussing a bit of SW here, I'll add that the only filter I run on my 27g reef is a biopellet reactor (which is essentially a biofilter that provides a consistent carbon source for improved growth).


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## aokashi (Jun 12, 2012)

Ive done plenty of such filterless tanks. I love to keep a flow but there have been tanks that are stagnant and still do very well. I've never had a problem with things breaking down in the tank. if its a dead leaf or something, they snail will be sure to process it further.


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## Dtitus1 (Jan 20, 2013)

funkman262 said:


> A little confused here. Why would breaking down the waste via bacteria be better than the plants actually consuming the organics? Plants are much more efficient at nutrient and waste removal than bacteria is, which is why more research is being put into constructing wastelands or algae ponds for the use in wastewater treatment in which bacteria removal is currently the conventional method. Certain species like duckweed varieties especially are being researched for their ability to remove heavy metals.



Plants don't remove waste, they remove the nutrients after the waste breaks down from the biological processes occurring in your tank. Not saying filterless won't work, but when you take out your main biological filter solid wastes are gonna build up. Like I said, like 1 or 2 small fish in a 10 gallon could probably work out nicely, but seems to be a method that people use for tanks that are mainly focused on the plants.


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## aokashi (Jun 12, 2012)

detritus really doesnt hurt a well planted tank


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## Django (Jun 13, 2012)

I'm sort of in between - in a 10 gal. tank I have an AquaClear 30 (adjustable from 10 to 30) at about 20 and I just have a sponge in there that I wash in tap water every week for mechanical filtration. I want the nitrifying bacteria to be in the tank with the plants, where all the action should be.


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## dprais1 (Sep 12, 2012)

Subscribed!


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## PaulG (Oct 10, 2010)

I don't use filters. They cost money to run, buy and you need to service them.

You have to make sacrifices with fish load however. I'm ok with this.


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## scapegoat (Jun 3, 2010)

Dtitus1 said:


> Idk, I still wouldn't do it, the reason saltwater works without a filter (I still run one in mine regardless) is because your live rock builds up bacteria colonies that break down the waste.
> 
> Your plants aren't going to break down waste into usable nutrients, they're just going to use them, but if there's nothing to grow bacteria on to break down the waste it's just gonna build up and look nasty.
> 
> Now there should be some bacteria in your substrate, but this isn't really an efficient place for them to colonize in large numbers, so it would work to have no filter if you had incredibly low stocking in livestock, but still I'd just have a filter and more fish.


You're forgetting the immense surface area within a planted tank; all those plants. bacteria grow all over them. water flowing over their leaves is being filtered/cleaned all the time. Think of it as a symbiotic relationship between some coral and the algae that grow on them.


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## Knotyoureality (Aug 3, 2012)

My 20g riparium is running without a filter or powerhead, heavily planted, heavily stocked with a juvenile BN pleco, a molly, six neon tetra, 3 amano, umpteen cherry culls, pond and malaysian trumpet snails (only a few huuuge ones, not enough food for them to reproduce thanks to the...) endless parade of females and fry from the resident black bar endler colony. Not a speck of algae, not even green dots on the glass. It gets a 10-20% wc every other week, more from habit than need. Substrate is fluorite with a scattering of aquarium gravel and small river stones, hardscape includes a variety of driftwood shards (3-4" long), a big hunk of dw for the pleco's cave and a large multi-branching bit of manzanita. No lack of surfaces for BB, especially when you add in the thick mats of aquatic roots from the riparium plants. 

My planted vases (3g and under) are tech-free. Including a heavily stocked 2.5g vase with 8 cherry shrimp, a gazillion scuds, a male/female breeding pair of hybrid endlers and anywhere from 4-14 fry at any given time.


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## Navyblue (Jan 1, 2013)

I think there is a lot of half truths being thrown around here.

Filters are useful for tanks without any means of nutrient removal, which are basically fish only tanks. It helps to break down ammonia to less harmful form (nitrate). I need to stress the word "helps" here, it is never a necessity. Nitrification can work pretty much anywhere, not just inside a filter. Tanks with means of nutrient export, namely planted tanks and some reef tanks, a mechanical filter is even less important.

A mechanical filter does not remove nitrogenous waste until you physically clean it, it merely breaks it down to less harmful form (nitrate) which will accumulate. Where as plants absorbs many forms of nitrogen compounds and remove them from the water. Altogether That is assuming the plants don't die and left to rot in the water. This is why it is possible to keep fish in a planted tank without water changes, without plants it is simply impossible. Therefore plant is a superior filtration to mechanical filter.

Fish poop on it's own is relatively harmless to fish. What is deadly to fishes is ammonia, which is constantly secreted by fishes through their gills. Fish poop and uneaten food is dangerous when they are decomposed by bacteria, which produces ammonia, which is deadly to fishes. Ammonia need to be dealt with as soon as they are available. They can be directly absorbed by plants.

As mentioned, nitrifying bacteria grows on all surface areas, and not just in a filter. A filter works by 2 ways. The first is to provide a growing surface for the bacteria. This is why filter mediums are porous objects, which has a high surface area to volume ratio. The second is the high water movement through the filter media heavily oxygenates these surfaces, a higher oxygen content can support a higher population of bacteria.

Both of those can be provided to a tank without actually employing an actual filter. The first though the use copious amount of substrate (which is typical in a planted tank), plant surfaces, or even porous rocks. In fact, unless you have a really huge filter, you are going to have a lot more surface area on your substrate than on your filter media. The second can be replicated through the use of powerheads (or even air stone), the higher the flow merrier, as long as your plants won't be uprooted by the flow and the fishes can take it.

Having a porous rock in a freshwater tank is different from the concept of using liverocks in saltwater tank. A liverock can have some denitrifying effect, deep inside it can form anaerobic regions that would house anaerobic denitrifying bacteria. This does not work in freshwater as freshwater carries a much higher oxygen content and anaerobic denitrifying bacteria can not achieve a meaningful population in a freshwater tank.

Also, apart from liverock, the popular methods for nutrient export in reef tank are algae scrubber and macro algae refugium. They work pretty much in a same way as using plant as a means of nutrient export in freshwater tanks. I personally keep reef tank with macro algae refugium for years without water change.


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## extrame (May 17, 2011)

hi, 
i run a tank with no filter and its been up for 16 months now. 
its heavily planted and have a lot of fish, snails, and shrimps in it too


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## scapegoat (Jun 3, 2010)

anyone running fitlerless hightech tanks?

would there really be a difference between high and low/dirt tanks as far as filter use? I mean, the filter does the same thing in either scenario.


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## Wy Renegade (Nov 29, 2011)

So the point has been made that if enough substrate/surface area has been provided within a tank for bacteria to populate, then the process of breakdown can occur naturally within the tank itself rather than in/on a filter. 

I would disagree with the notion that a freshwater tank has a higher oxygen content than a saltwater tank. Oxygen concentration has very little to do with dissolved substance concentration in water, it is mainly about temperature, therefore a fresh or saltwater tank with equal flow rates and equal temperature should have about the same concentration of dissolved oxygen. The primary difference is in the use of anaerobic areas within rock and substrate (often controlled by substrate depth). Certainly in a freshwater tank with a fine enough substrate there are anaerobic areas that support denitrifying bacteria. I personally think that this is simply an area of freshwater tanks that hasn't received much interest. Anaerobic is anaerobic, regardless of the oxygen content of the water, and if I can create anaerobic areas with a freshwater tank then those areas will support denitrifying bacteria. 

The ratio of surface area on filter media vs. that of natural substrate and rock is also an often debated question. In reality, most modern filter materials have significantly more surface areas for bacteria colonization than the normal substrate that is included in aquariums, which is why they are significantly more effective at nutrient export. It that wasn't the case, everyone would still be using undergravel filters, as they take advantage of the normal substrate space available for bacteria colonization. The reason we've switched to modern HOB and canister filters is because they provide more surface area for bacterial colonization than most substrates and are therefore more effective a filtration. A quick good search in regards to surface areas of ceramic filter media or even bioballs bears that out. 

All that said, there is no reason that running a filterless freshwater planted system should be any more difficult or any less successful than running a filterless reef tank.

Personally I think that flow rate (as it is in reef systems) is going to eventually emerge as one of the major factors.


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## l8nite (Aug 29, 2012)

I'm interested now. My 110G has three filters on it right now (Eheim 2217, Fluval 405, and Fluval 403).

Would be pretty great if I could cut that down to one for just the inline CO2 & heater...


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## PaulG (Oct 10, 2010)

l8nite said:


> I'm interested now. My 110G has three filters on it right now (Eheim 2217, Fluval 405, and Fluval 403).
> 
> Would be pretty great if I could cut that down to one for just the inline CO2 & heater...


What's your stock?


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## l8nite (Aug 29, 2012)

PaulG said:


> What's your stock?


2x angelfish, gourami, red tail shark, 19 neon tetra, 7 black skirt tetra, 9 guppies, and 2 otocinclus


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## dprais1 (Sep 12, 2012)

Wy Renegade said:


> The ratio of surface area on filter media vs. that of natural substrate and rock is also an often debated question. In reality, most modern filter materials have significantly more surface areas for bacteria colonization than the normal substrate that is included in aquariums, which is why they are significantly more effective at nutrient export. It that wasn't the case, everyone would still be using undergravel filters, as they take advantage of the normal substrate space available for bacteria colonization. The reason we've switched to modern HOB and canister filters is because they provide more surface area for bacterial colonization than most substrates and are therefore more effective a filtration. A quick good search in regards to surface areas of ceramic filter media or even bioballs bears that out.


Every once in a while I search for some evidence to support the whole "high-tech filters are better than a sponge filter" theory but I have yet to ever find any.


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## John K (Nov 12, 2011)

I never use filters on my tanks, just power heads for circulation. They're all set up as Walstad tanks -potting soil capped with gravel, lots of plants. I just tore down the first one - a 10 gallon that had been running for 3 years just fine. My largest is a 50 gallon with 5 Pearl Gouramis, 13 Rummynose Tetras, 3 adult Bolivian rams. Nitrates stay between 5-10 with only occasional partial water changes.


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## Beer (Feb 1, 2012)

You have to have a decent plant mass for this to work.
To have no water movement at all, would have to be determined by the inhabitants and types of plants. some fish need water movement to be happy. Some plants grow too slow to do well without water movement to remove sediment and discourage algae growth. A good cleanup crew would be essential too (shrimp and a moderately small snail population). People mention water movement for nutrient dispersal, but I think an active fish population can help provide that. Nutrients aren't being depleted that rapidly in lowtech tanks.
I wouldn't recommend this though for tanks that don't get observed frequently. Just setting it up and leaving it to its own devices could be disastorous for the inhabitants.

NavyBlue, FYI fish don't actually put out waste from their gills (other than CO2). Gills are strictly for breathing. Look up the osmotic process, which is where GH and KH come into play for proper hydration and expultion of waste for freshwater fish (for salt water too, but salt water fish actually drink water constantly and also use the process to regulate internal salt content)


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## Wy Renegade (Nov 29, 2011)

dprais1 said:


> Every once in a while I search for some evidence to support the whole "high-tech filters are better than a sponge filter" theory but I have yet to ever find any.


I think the debate between effectiveness of high-tech filters and sponge filters is a different conversation than the effectiveness of high-tech filters vs. substrate. There is a lot of evidence to show that modern high-tech filters provide more surface area for bacteria colonization than the average sponge filter, however sponge filters not only provide a surface for bacteria growth for biological filtration, but they also provide direct mechanical filtration as well. Therefore a comparison of effectiveness between the two would be pretty difficult to accomplish. 

Some references for you to look at;

http://www.fishchannel.com/setups/ponds/biological-filter.aspx

http://www.biofilters.com/webreview.htm

http://www.wetwebmedia.com/fwsubwebindex/fwfiltration.htm

http://scialert.net/fulltext/?doi=jas.2010.1146.1150&org=11

http://www.pondshop.com/catalog/megalite.htm

That last one is an advertisement, but contains information on the actual surface area of bacteria and sand grains.



Beer said:


> You have to have a decent plant mass for this to work.
> To have no water movement at all, would have to be determined by the inhabitants and types of plants. some fish need water movement to be happy. Some plants grow too slow to do well without water movement to remove sediment and discourage algae growth. A good cleanup crew would be essential too (shrimp and a moderately small snail population). People mention water movement for nutrient dispersal, but I think an active fish population can help provide that. Nutrients aren't being depleted that rapidly in lowtech tanks.
> I wouldn't recommend this though for tanks that don't get observed frequently. Just setting it up and leaving it to its own devices could be disastorous for the inhabitants.


I think another factor you would need to consider is substrate. If for example you are using a very fine sand with no to minimal water movement, then debris is quickly going to settle and fill in the void space and surface area of the sand, reducing your effective aerobic zone for bacteria colonization to only the top surface area of your substrate.



Beer said:


> NavyBlue, FYI fish don't actually put out waste from their gills (other than CO2). Gills are strictly for breathing. Look up the osmotic process, which is where GH and KH come into play for proper hydration and expultion of waste for freshwater fish (for salt water too, but salt water fish actually drink water constantly and also use the process to regulate internal salt content)


Actually, not quite.

http://www.marietta.edu/~mcshaffd/aquatic/sextant/excrete.htm

Just a brief introduction. A quick google search will quickly reveal lots of scientific abstracts on the subject if you want to look into it further.


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## dprais1 (Sep 12, 2012)

I'd say this qualifies as evidence

http://scialert.net/fulltext/?doi=ja...46.1150&org=11

I think i was too brief, so let me explain.

You have a 2 20 gallon tanks both identical in terms of plants and fish and one tank has a sponge filter and one is running a big canister. 
After a year which tank is cleaner? They should be the same because bacteria has colonized the tank and filter media to the point it needs to. More surface area allows for more bacteria but there will still only be as much bacteria as there is food to feed it such that much of the space will in effect be wasted.

I personally feel that these high tech filters and the desire to have them is driven solely by the manufacturers of said filters.

My daughter wants a laptop, the best, fanciest, and most expensive. Why? because it is the best. Okay fine. Why does she need the best? To send emails, watch You-Tube videos, and play around on the net. 

Having the best and needing the best are very different things.

So a big, fancy filter might be better, but that does not make it more effective.


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## Wy Renegade (Nov 29, 2011)

dprais1 said:


> I'd say this qualifies as evidence
> 
> http://scialert.net/fulltext/?doi=ja...46.1150&org=11
> 
> ...


Gotcha! And yes, I agree with you a 100%. Its a very similar as the question of cycling a tank, either salt or freshwater.

How do I cycle my tank? 

Set it up and add ammonia to it till the ammonia gets converted into nitrites and then nitrates.

How much ammonia?

X ammount for a X gallon tank?

Why? 

Because X amount will give you enough bacteria to support a fully stocked tank of that size.

What if my tank isn't going to be fully stocked? What if I only want a few fish?

Its always been my thought that a full cycle is rather silly without finding out what the stocking intentions and time frame of the individual are. Why go to all the time and trouble of fully cycling a tank, only to allow that built up bacteria population to die back when only a few fish are added to the tank to begin with anyway?

That, I think, is a subject for a different thread perhaps?


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## Rich Guano (Jan 19, 2012)

Wow, lots of great thoughts on this subject. I appreciate everybody who has commented and/or offered other areas of study.

If we look back say 100 years ago, what kind of filtration methods were being deployed then? Does anybody have any documented examples?

In regards to my opening post, are our plants in competition with the filters? Plants seem to be the higher life form, but do they out compete bacteria for nitrogen?


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## funkman262 (Nov 11, 2010)

Rich Guano said:


> In regards to my opening post, are our plants in competition with the filters? Plants seem to be the higher life form, but do they out compete bacteria for nitrogen?


There isn't much competition when it comes to the nitrogen source; plants are more efficient at N-uptake.


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## jeremy va (Dec 22, 2012)

I don't know anything about saltwater but I do know that in the freshwater area the success of a tank, from an aesthetic standpoint, is in the eye of the beholder. It seems to me that the decision to go with hi-tech, lo-tech, no-tech or somewhere in between is driven by the desired aesthetic outcome as much as anything. In other words, it depends on what you want. Call me nuts but I bought an eight or ten gallon glass cylinder about 8 years ago at Pier One. I think I put some laterite in the bottom, then a couple inches of eco-complete and an inch or so of grungy mulmy stuff has built up over the years. It sits next to a window and is jam packed with healthy looking Vals that reach to the top -- say two feet. I don't change the water. No filter, no circulation, no extra lighting no ferts -- and no fish except the occasional one who needs a temporary home. I happened to test the water out of curiosity the other day using a test strip and it was the same as my well water. It is really a big vase that has planera, some hydra and some of those little copepod things and a whole lot of other inhabitants that are only visible with a microscope, I'm sure. I had scuds in it but there was a population explosion and subsequent crash. Oh, and there is an amano and nerite in there. In the summer it can get pretty green (and it is a pretty green) but it always sorta fixes itself and, come winter, it clears up. I think it is interesting to watch the way the algae ebb and flow and, all in all, the tank pleases me. (I also like the completely unnatural "nature" tanks that are sustained only be the careful and exacting control of their parameters -- but that is a completely different aesthetic.) I think that when the algae bloom dies it must provide food for the Vals but I've not bothered to research it.


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## l8nite (Aug 29, 2012)

Something anecdotal, but I removed 1 of 3 canister filters from my tank last week as well as about 75% of the filter media from the other 2... and now my plants are going gangbusters.


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## danielt (Dec 19, 2012)

Great thread! Much appreciated for the deep analysis of some of you!

From my experience I would be inclined to say bacteria *can* outcompete plants at N uptake. Bacteria works without light as well. Whatever Ammonium gets in the water it will be taken by plants during the photoperiod, then comes the night. Bacteria will strip whatever Ammonium is in the water and plants will need to consume energy for Nitrate processing.

Unless a soft spot is hit with the bio load there will be problems in the long run. Currently I'm facing a constant water acidifying effect because I have an Eheim 2080 hooked to a 300L tank. Which is 4 times smaller than the tank size for which this canister was designed.

Bacteria generates H+ as a byproduct of Ammonium and Nitrite oxidation. I will soon start a new tank to test this method. Will use just a powerhead for water circulation, some lava rock bits, zeolite, potting dirt and inert gravel. I have some AquaMedic Volcanit leftovers.


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## Django (Jun 13, 2012)

I tend to think that Nitrates are an indication that Nitrification bacteria have been at work. No Nitrates tells me that plants are doing their job. I know we don't usually get zero Nitrates, but that's when nitrates have come in.

In the end, it's hard to offer a conclusive answer. I think threads like this are good to help people develop their own there own theories, and maybe sometime an answer.


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## danielt (Dec 19, 2012)

It got my wheels spinning at least 

No Nitrates might also mean bacteria is killed with water changes straight from the tap.

I know a buddy of mine that realized he was killing his bacterial flora with tap water


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## funkman262 (Nov 11, 2010)

danielt said:


> It got my wheels spinning at least
> 
> No Nitrates might also mean bacteria is killed with water changes straight from the tap.
> 
> I know a buddy of mine that realized he was killing his bacterial flora with tap water


He must have been killing his fish too between the chlorine from the tap and ammonia from no bacteria.


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## danielt (Dec 19, 2012)

Fish no, some RCS occasionally and low breeding. Few females berried. The weird thing is that he did this to a Discus tank as well. Didn't lost any fish and he has a pair that frequently spawned.

The rate spawning rate increased after he started to mature the water for a couple days before the water change.


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## danielt (Dec 19, 2012)

Fish no, some RCS occasionally and low breeding. Few females berried. The weird thing is that he did this to a Discus tank as well. Didn't lost any fish and he has a pair that frequently spawned.

The rate spawning rate increased after he started to mature the water for a couple days before the water change.


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## Saxtonhill (Dec 28, 2012)

jeremy va said:


> I don't know anything about saltwater but I do know that in the freshwater area the success of a tank, from an aesthetic standpoint, is in the eye of the beholder. It seems to me that the decision to go with hi-tech, lo-tech, no-tech or somewhere in between is driven by the desired aesthetic outcome as much as anything. In other words, it depends on what you want. Call me nuts but I bought an eight or ten gallon glass cylinder about 8 years ago at Pier One. I think I put some laterite in the bottom, then a couple inches of eco-complete and an inch or so of grungy mulmy stuff has built up over the years. It sits next to a window and is jam packed with healthy looking Vals that reach to the top -- say two feet. I don't change the water. No filter, no circulation, no extra lighting no ferts -- and no fish except the occasional one who needs a temporary home. I happened to test the water out of curiosity the other day using a test strip and it was the same as my well water. It is really a big vase that has planera, some hydra and some of those little copepod things and a whole lot of other inhabitants that are only visible with a microscope, I'm sure. I had scuds in it but there was a population explosion and subsequent crash. Oh, and there is an amano and nerite in there. In the summer it can get pretty green (and it is a pretty green) but it always sorta fixes itself and, come winter, it clears up. I think it is interesting to watch the way the algae ebb and flow and, all in all, the tank pleases me. (I also like the completely unnatural "nature" tanks that are sustained only be the careful and exacting control of their parameters -- but that is a completely different aesthetic.) I think that when the algae bloom dies it must provide food for the Vals but I've not bothered to research it.



Fascinating! I would like to try a tank like that...on a small scale...

Subscribed to this thread


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