My cunning Plan

Hi. So I decided to start keeping axolotls. For a number of reasons.

And for a number of reasons I have decided I am going to experiment with a "natural aquarium" set up and run live plants as my primary filtration method. (I've seen some threads around here and also on the natural aquariums forums about this already).

As it turns out I am convinced I have all the available resources to do this because I happen to already be an experienced professional who grows and sells Water Plants for a living.

This means I have an unlimited supply of fresh plants, fish, insects, tadpoles and other things to stock, clean and feed my tank of axolotls. The only real problem is that while I run any number of fish, plants and amphibians outside in my outdoor ponds using basically identical methods to "natural aquarium" enthusiasts my experience is all geared toward outdoor plants, and the fish and the amphibians are just minor utilities for pond cleaning or guys that just turn up and hang around.

About a fortnight ago I set up a tiny experimental fish bowl (I had a large glass ball just lying around, like you do). Just to try out and see how sediment settles and whether a few plants I thought would be good selections would run well.

It's about a 30cm diameter ball half full of water. I based it with a substrate of about 0.5cm of clay loam (for the plants), fed that with about 5 tiny pellets of nutricote slow release fertilizer (the only slow release fertilizer available around here that actually works in the water), planted in a mat of Brisbane Water Lawn and a few runners of Rainbow Nardoo, placed some very large gravel pebbles on that and threw in some water fox tail loose. Then I stocked it with an expendable brown goldfish from one of my ponds, to get the thing cycling, feed the plants etc.. The whole thing gets several hours of reasonable sunlight from a northward facing window. Oh and of course I filled it with natural rain water (I always have an unlimited supply) and about 1 third pond water from one of my best ponds (no limit to the supply of that either). I neglected to wash things especially well. And I threw in a native water snail.

The gold fish has run well for the last two weeks with no water changes, no filtration, no bubbler. Just plants and a tiny amount of food when he looks like he might actually eat it. The water quality cleared up very nicely (initially rather murky, but it only took several days to settle and clear nicely. All the plants have taken very nicely. My digital electrical conductivity is telling me that salinity levels are down in the 40-50 parts per million range and seem to be holding pretty stable.

If I wanted to I suspect I could run a (small, cramped and unhappy) axolotl in that right away, but that ISN'T the plan. In part because that was just a trial tank (I might use it for holding live food or separating axolotls while they are little) and in part because I am off to china for a fortnight in the near future.

Instead the plan is a cheap 3 foot class aquarium I bought the other day. I have set it up in a similar manner to the trail, with some eel grass and another plant (doesn't have a common name) and have it running 4 disposable gold fish. It's still lightly murky from unsettled/unfiltered sediment but it's only about 2 days old. The plan is that when I return in about three weeks I turf out the goldfish and stock the tank with some young axolotls I may have hopefully sourced in my area.

In case of emergency I have among other things a Peace Lilly to use as an additional filtration plant (I understand it has been rather successful for others) and a bubbler that I would really rather not use (I don't THINK I will need it for oxygenation or circulation), but could run at a moments notice if necessary.

Mostly I think I have enough of a handle on things to run this experiment with minimal risk to my axolotls and a pretty good chance of setting up a really awesome organic (and lower maintenance) environment for them.

1) Do axolotls tend to dig in the mud? I mean aside from just blundering around stepping on things and bumping stuff. Do they actually try and DIG? If so I may need more giant gravel/established water lawn.

2) Is my digital salinity meter any use? I happen to have one already, we use it to monitor salinity levels in outdoor ponds and to track diluted fertilizers in certain water plant containers. Presumably it at least has some relevance to Nitrate levels, and I THINK it's reading should be at least partially relevant to Nitrites, but suspect it may be moderately unsuited to measuring what I need to.

3) Live Food Diet ? I have an unlimited supply of mosquito larvae, water beetles, tadpoles, crickets and small fish (among other critters). I plan to feed these to my axolotls and only really use pellets, beef heart or purchased foods during the brief times of year that it is a bit harder to catch live food or as a light supplement. Are there any particular things to avoid, other than based on size of the axolotl, or because of the small risk of disease, which as far as I see it should be entirely off set by the benefits of a heavily live food diet?

4) Things I haven't thought of ? I am sure there are some. I know I haven't included hides and a few other details yet which I plan to add along with the axolotls, but even so there is probably something else...

Oh and I might include some links to some pictures (to some outdoor examples) of the plants I used...

Brisbane Water Lawn and Rainbow Nardoo


And Water Foxtail (this one should be familiar to most of you aquarium people)


I might get some pictures of the actual aquariums together later, but my first attempt came out terrible. The lighting is just really bad for photography (OK for the plants).

OK here are some pictures of the tanks.

The general position near a window for natural sunlight (important for the plants).

Even in this picture you can see the difference in water quality between the established experimental bowl and the new main aquarium.

The experimental bowl, I hope you can see the (apparent) water quality and health of the plants.


And now a section of the final big tank that went in about two days ago now. Still a bit murky. Should settle soon (if not those fish may be going back out and more plants will be going in until it does).

A couple of things, those rocks in the last picture i would probably get rid of, they will be fine for juvi axies but could get swallowed up by adults which = death. Another thing, axolotl's need 0 ammonia and you will have to keep ontop of the water and checking that it is all good with no filter in there.
Yes they do dig, mine used to love digging in the sand.

And also with the live foods they themselves can have harmful bacteria/diseases that can be harmful to the axies, also i don't no if this is normal but once my axies had live food they would not eat pellets soo keep that in mind.

sounds good.

please remember though axies are not fish and must be treated accordingly.

they need 0 ammonia and 0 nitrite. they don't have scales and ammonia and nitrite will "burn" their skin and you will see them shed their slime coat and you'll also see receding gills as a result. filtration is highly recommended or if you choose not to filter, daily water changes of 20-30%.

as for your choice of plants. axies have no eyelids and need a darker or at most a dimly lit environment. they are rather sensitive to light. this can reduce your choice of plants.

axies need a fine substrate... washed play sand is the preferred option. as above, normal aquarium gravel causes ingestion and large pebbles trap waste and mess with water chemistry as they are very messy creatures.

as for filtration, they don't like fast moving currents. a established sponge filter should do fine.

I have a plant filter on my axie tank, I grow peace lilies in the trickle filter above the tank and I consistently get 0 on all readings. I have been doing this for several months now.

I think the very smallest of the rocks was something like 3cm give or take a bit. I was hoping that was big enough. The notes I had read seemed to just say not to use finer gravels.

My biggest concern with the Ammonia is simply that I suspect I can't test it with my existing device and will need to get a testing kit.

I agree with the other posters. Any stones smaller than your axolotl's head are a risk to them.
Axolotl do dig and snuffle about, mine regularly re-arrange a carefully arranged tank.
One other thing to take into consideration is the tank temperature, axolotl need cool water, ideally below 20 degrees.
I very much like your idea, and I suspect you'll find solutions to any problems

iChris said:

large pebbles trap waste and mess with water chemistry as they are very messy creatures.

Click to expand...

The natural aquarium notes I read seem to indicate that people running heavily live planted aquariums and using the plants for filtration are actually suggesting bigger rocks trapping and hiding waste as it settles into a the soil substrate underneath the rocks where it then feeds the plants as the actual intended way to run this sort of set up. (man thats a long sentence)

as for filtration

Click to expand...

The idea is that it's a plant filter, but sort of a ubiquitous one with a lot of (established) plants throughout the aquarium, and maybe some disposable floaters I can change out as required since I have an infinite supply. With any luck the Brisbane water lawn will take and the entire floor of the tank will be a (rather hungry) plant filter doing the bulk of the work.

I've had a lot of experience with using plants for outdoor pond filters and generally find them to be flat out superior to most (out door) artificial filtration methods. My concerns with this experiment are more along the lines of...

1) Can I keep the plants healthy in an aquarium?
In an outdoor pond, even a small pot of water the same size I know from experience I could easily plant out this sort of set up and it would keep the water quality at a level basically indistinguishable to rain water. But if the indoor conditions make the plants die or even fail to thrive then that isn't going to work.

About all that can be done for this is to experiment with it. Some of the plants I am working with aren't commonly used in aquariums, but the local aquarium plant trade is... somewhat shoddy and I am convinced my pond plants are better selections than some of the alternatives on offer.

2) Will the axolotls co-operate?
Even outdoors there are certain critters that will ruin a perfectly good plant filtered pond. Coy Carp or Yabbies for instance will destroy water, rip up every plant they can find and then poison themselves. I have basically no idea whether Axolotls will be like that, or like something more co-operative, like gold fish, frogs or eels.

The digging sounds like a problem. I'm probably going to need more pre-established waterlawn. I just hope they don't decide to dig through a thick fibrous mat of plant matter.

3) Will lighting be a problem?
From the pictures you can see I placed the aquarium near a window for natural sunlight. There is no artificial lighting beyond whatever the humans in the room are using. The window will provide a great deal of sun for a bit more than the first half of any day. Even with relatively low light tolerant plants this is what I suspect is pretty close to my bare minimum to get this setup working.

Now the floor of the aquarium falls below the window sill and should receive SOME protection from the direct sunlight. But not that much. The plants should provide a great deal more shelter from direct light, I could readily carpet the entire water surface and a good portion of the volume in between, but still, far from perfect.

I will also be adding some hides for the axolotls once the plants are more established and the water settled.

I was aware that axolotls don't like sunlight, but I don't really know to what precisely what degree, and I fear that this is about the best I can do.

Also how are you keeping the tank cold?

I would go against the whole big pebbles and waste to make a substrate, as this for axies can mess with water, i no that plants will suck up some of the bad stuff but i would not go this for such sensitive animals as axies, perhaps better for live bearers.

And with the plants i have never had experience with what you are trying to use as the plants so i cannot comment on how they will do within and indoor tank setting.

With the axies cooperating, they will try and mess it up as they like to dip, i would suggest you have an extremely established lawn otherwise it will be destroyed rather quickly, i think.

With the light, having it near the window you could run into problems like algae also yer axies don't like the light and i don't no if the constant light will be ideal for them. Again, never had experience with an axie tank in direct sunlight. But i think if you provide enough cover 'shade' and hides for the axies it would be fine. I think that you can achieve that with stems at the back of the tank.

Keeping it cool may well be an issue in summer. It gets hot around here. However having taken temperature readings of outdoor ponds and containers in much more exposed conditions in the past... I should be pretty close. It IS in a double brick building that itself is pretty cool and there are heavy curtains that can be closed. And also plants will actually help cool it (to a small degree).

It will likely take heat wave conditions to be problematic. But the problem is there WILL be heat waves. Basically I won't have a firm idea whether maximum temperatures will drift out of range until it happens. Fortunately monitoring temperature isn't hard and there are measures I could take in case of emergency.

As to algae... if I have algae then water quality is already in trouble. Algae isn't caused by sunlight alone. If the plants are doing their job they are suppressing the algae and out competing it for nutrients (and light) as a by product of filtering the water.

The co-operating thing and apparent concern over rather large rock swallowing worries me. I may have to do some more planting and messing about with my substrate. Fortunately I have any amount of plants and any amount of larger rocks and am only limited by the maximum size I can fit into the tank.

As to getting the plants well established at least in that particular field I am fairly confident and the trail suggests that it takes about two weeks. Regardless I won't be stocking it until at least three weeks or more because I am off to China in the mean time. I may have to wait even longer for the sourced axolotls to reach a large enough size for it to be reasonable to move them.

Come to think of it the size of the axolotls should help with their potential destructive rampages and rock swallowings. Even a heavily planted aquarium will require a periodic cleaning out and replanting, it will likely manage well more than a full maintenance run until the axolotls reach larger sizes.

Ok so with the pond readings that is not really relevant as bigger bodies of water take longer to heat up / cool down so they are alot more stable then a small tank in comparison. Where abouts in AUS do you live?
I personally would be going a chiller, its the best and only way.

The rest is totally up to you, as long as you can keep temps low and ammonia and nitrites at 0 then thats all they need water wish, and if you provide adequate hiddy holes for them and cover from the light they will be fine.

Personally i would never do an unfiltered tank for these guys, i have done unfiltered tanks before with things like betta's and live bearers but would no even consider it for these guys PERSONALLY. But that is 100% up to you, it will be a learning curve, as it was for me the 1st time i kept these guys.

Oh I've kept axolotls before, when I was a kid. (Even kept one for a couple of years in an unfiltered outdoor container way smaller than this one... until a surprise German Shepherd appeared and ate it, maybe that should be added to the incompatible species lists...). Reading up on them now I'm surprised how successful I was.

As to local conditions we COULD hit 40 the odd degree day. But even then indoors it should be hard to top 30, and at that point a tank that size with the curtains to block direct sun should (I hope) be somewhat cooler and should hover just at (or if I am unlucky just OVER) the maximum temperature for axolotls. Which if I recall was what? 24? Unfortunately I wouldn't be surprised by temperatures of 26 or 28. If I need to I will have to get a chiller, but I can also move the aquarium during a hotter portion of the year or use the dodgey ice bottle method if it's just one or two days.

Do not put the pant fertiliser in the tank if thee is going to be axolotls in there. They have a slimy membrane for skin and absorb everything! not even fish medications are safe for them, let alone a fertiliser, organic or not.

Plants make a fantastic natural biological filter. Once established they should keep your nitrates and ammonia at 0. Peace Lilly’s are fantastic for this, grow them out of the top of the water. The only thing plant filters lack is physical waste disposal... they can't suck up the chunks of poo. You will have to remove them somehow (turkey baster works great) because they are a constant source of ammonia... and who would like to swim in their own poop?

And temperature/light! Plants are FANTASTIC for the water except as you said they thrive on light. And unfortunately axolotl's do not, in fact they hate it. And with the sun comes heat... and they hate that too. Water plants need light, however peace lilly's are incredibly hardy, and they can survive in low light conditions. Java moss is also good like this too. If you want to use plants, you need to find the right ones which can cope with the axolotls living requirements. Specific plants can be chosen to match the living requirements of the axolotl, however axolotls can not be chosen to match the living requirements of plants. They are quite fragile and need specific care.

Good luck

Well I am back from my holiday to China.

When I returned things were both good and bad.

The extra small experimental aquarium had a rather high salinity reading (well, high by the standard of the very low salinity water I have). Indicating that some chemical waste had actually built up in there with the one goldfish resident in the experiment. So I just did a partial water change and that cleared up no problem. By the rate it is currently rising (now with an additional tiny gold fish) it probably will need partial water changing once every one to two weeks. I'm still running the experimental aquarium in case I suddenly need it for something.

The big aquarium which had had 4 gold fish in it to cycle and condition it a bit while I was away had really very nice readings. However it had the rather unusual problem of persistent suspended sediment of some kind in the water.

I blamed the goldfish for being put in before the sediment had settled originally and turfed them out. I also added even more plants, carpeting very nearly the entire bottom of the tank with water lawn and throwing in some more loose washed foxtail (as it is particularly good at removing both mineral and organic sediments/suspensions in water). I Performed a water change and waited.

A few days later Sediment stubbornly persisted. I performed another somewhat more careful water change (a very gentle and slow fill to avoid stirring up any substrate or settled sediment that escaped a wipe down) and partial cleaning of the tank. Which helped a little. But it still did not perfectly clear the suspended sediment discoloring the water.

Now at that point I was being pretty fussy. From everything I gather about axolotls the little bastards would probably PREFER to just a light hint of murk. But I want crystal clear water. So I break and buy a sponge filter I can stick on my disused emergency air pump.

The basic physical filtration from the sponge makes short work of the small amount of heavier sediment that I readily attribute to the loam substrate for the plants (though why it decided to be problematic in this tank and not the test tank I will never know). However a small amount of very fine and pale something remains suspended in the water.

My best guess is that it is a very VERY light clay, a tiny piece of rotting plant matter, some actual lime or even some duck poo (that somehow escaped thorough and multiple plant washings). I was careful but it's probably something introduced with the plants or substrate.

Certainly PH readings in the big tank while far from bad were higher than expected, and higher than the original test tank. So I fixed the PH side of things promptly by throwing in small amount of a plant that brought the PH down from about 7.9 to just around 7 or slightly under overnight. Yes I have a plant that does that. It isn't even uncommon.

In addition to all this I have bought a proper chemical test kit for Ammonia levels. I am still confident my conductivity meter should give me sufficient information about nitrate and nitrite levels to at least know if I need to buy a kit to test for them specifically. But the Ammonia levels seemed like something I would need to get a separate kit for and which would be a good indicator of any serious troubles.

All tests for Ammonia over several days have been good.

With all chemical indicators having been actually very good for the entire trail of the big tank and the filter having picked off the worst of the sediment I decided that the very light remaining suspension in the water was not pathogenic and would best be cleared up by routine maintenance as the tank settles into actual use. (in the long run I still hope to be able to just turn off the sponge filter)

So I decided to go pick up those baby axolotls I sourced. I'll write up another needlessly detailed post in like five minutes or so about those guys.

So I purchased four baby axolotls that were maybe about 3cm long at most. I got some reasonable variation in colour, I think.

It is worth noting that while the pet shop aquarium I got these from doesn't seem to know all that much about Axolotls they DO have some of the happiest axolotls I have seen in a commercial aquarium.

They had been feeding them on a mix of black worms (the tiny aquatic ones if that saves any confusion) and had even convinced them to eat some fish food flakes. The baby axolotls seemed fat, healthy and happy and are just beginning to develop rear legs.

I have been running the babies in the big tank for three days now (I figured it's best to get them used to it from an early age, whatever difficulties or risks that may entail). The black worms (I got a few as back up food) seem impractical in the large plant filled tank where they can escape and hide from the small number of axolotls.

Fortunately I have access to a lot of mosquito larvae and even large numbers of very (VERY) small tadpoles.

Also fortunately the baby axolotls seem to be managing to hunt down the mosquitoes and tadpoles and remain well fed.

Unfortunately I DO seem to have lost one baby axolotl. I don't mean it's dead. I mean it's missing. I've sighted three out of four of them pretty easily all the time. But I am pretty sure I haven't seen the fourth one in the last three days ever since I released them in there. So the one that I was hoping was a melanoid wild either looks just like the spotted wild and takes turns being seen, is dead, or is just really really sneaky.But then there does happen to be a huge amount of plants for such a tiny axolotl to hide in in such a large tank.

There have been no signs of poor health (among the visible axolotls) and if anything I'd swear I've seen the spotted wild at least visibly grow over the last three days (I'd swear it's gained as much as 5mm of tail length). The light suspension remains present but all daily chemical tests indicate that water quality is remaining persistently good. Food supply doesn't seem to be a problem and I am considering just chucking out the stash of annoying black worms.

So my biggest question at the moment is basically just this...

Q: How long do I wait before I declare the missing axolotl permanently MIA? Seriously. I know he is tiny, but how long could he possibly hide for? The others aren't even trying to hide.

Oh yeah. And about that sponge filter.
Q: It's a sponge and it's in the tank, no cannister or external cannister or anything. So that means if I want to I can just turn it off right?
It isn't the main source of chemical filtration in the tank, it won't be the main colony dealing with the nitrogen cycle, and it's in the tank itself anyway so it shouldn't go toxic. So I can basically just turn it off if I don't think it needs to be running anymore, right?

Just wanted to add that it does take bog plants like peace lilly a few days to get acclimated to their roots being in water all the time. It took mine about 2 weeks. Plant filtration could very well run your tank, that's basically what I run mine off of, I would advise adding a water bubbler or something to oxygenate your water, and at least move it around a little bit. I found out a while ago that in my extremely densely planted tanks my fish mysteriously died overnight whenever I decided to turn off my water bubbler. Because plants use oxygen when there is no light, i'm assuming the deaths are related to the oxygen uptake, because the water quality was always perfect in those tanks.3
edit: looks like we posted at the same time. I'd make sure to run your sponge filter on at least at night to make sure your axies get oxygen, just in case. But like you said, the main filtration is the plants, it's just a good idea to have a little water movement in the tank. My axolotls like to hide in the craziest places, however one problem with a planted tank is if things do die they can vanish pretty quickly(for instance I lost a guppy in a ten gallon tank, i'm pretty sure it died). If your tank has any hides try moving them around to see if your axolotls is just super sneaky.

i wanna see some pictures of this, because it sounds absolutely awesome.

OK so here are some pictures. http://www.caudata.org/forum/members/mathew-albums-grand-experiment.html

You should see the murky milky suspension I am having trouble with (but deciding to disregard). A mass of confused foxtail. The majority of the tank carpeted in water lawn (which seems to be just barely nicely established). The muddy substrate (a risk but it should help the water lawn and in the long run be swamped by it. The rocks the forums don't like (they can go out when the axolotls get bigger). And a lack of hides (they were going to go in but the small axolotls seem more keen on the foxtail and the weeds than on proper hiding holes, I even put in a trial hide in case they wanted to hide from the sunlight, they totally didn't use it).

just make sure you keep a close eye on the water parameters. While plants can filter a tank, I actually found that aquatic plants are not as effective as bog plants that only have their roots in the water. Your tank looks pretty well planted, but you don't want to rely on the plants for filtration and then find out you didn't put enough in to handle the bioload. Although in your case adding more plants doesn't seem like it will be a problem at all.

Your observation about bog plants and aquatic plants is probably fairly correct.

All (live and healthy) plants in the water provide filtration and other benefits. But some are significantly better than others. And what really does it well is nice fibrous root masses with large amounts of surface area compared to their volume. Basically a nice plant sponge.

Foliage in the water is certainly pretty and does improve water quality, but it's nothing compared to those roots.

Now there ARE aquatic plants that form roots in the water. But they aren't very popular in aquariums because they don't look pretty or something. A lot of other bog and even aquatic plants have very similar roots but the way in which they are usually planted in aquariums with limited space and shallow or no soil/silty substrates means those roots can't really grow.

A suspended bare rooted hardy bog plant like the peace lily would easily produce some of the best fibrous root growth for aquarium filtration. But there are quite a few plants that could be grown like that, most reeds in particular would do well in that role, but so would almost any and all bog plants. The problems lie in cosmetics, size and hardiness to indoor conditions, and by far the first two are the biggest hurdles.

Instead I hope to get my fibrous root mass from the water lawn on the aquarium floor. It's established, the axolotls aren't attacking it too vigorously (yet) and while it looks all green and leafy it is important to note that unlike some water plants this particular one has tangled mat of hidden roots about the same mass as that thick lush lawn of foliage. And it doesn't rely on too much soil substrate in order to produce that mat.

It is only just established so if you look at the pictures you will see a few stray roots or the occasional poorly settled root mass from the initial planting. As long as the water lawn continues to grow it should form a pretty hefty filter. Indeed if it does particularly well then in all seriousness it could eventually fill the entire volume of the aquarium without thinning.

So anyway current filtration by plants is basically.

Primary Chemical Filtration and waste disposal -> Water Lawn

Sediment and secondary Filtration -> Foxtail (loose floating, has no roots seems to gather and feed of floating sediment and other suspended stuff, very good for clearing up "cloudy" ponds, very fibrous leaf mass which MUST somehow double as roots since it doesn't actually have any)

Decoration and clearing up oily surface scum -> Rainbow Nardoo (This fern has pretty spiral fern shoots under the water, is hardy as hell, and has four leaf clover lily pads on the surface. Don't ask me what it is about lily pad type plants but they seem to help clean up oily scum on water surfaces)

More surface clean up -> Azola

Decoration and not much else -> Eel grass

I may run some more or other plants later for habitat, or decoration. I'm thinking I may even run a bowl lotus in there for pure cosmetics (and some heavy duty nitrate removal) for a few months in summer. (but no longer than that because it could actually worsen water quality if it winters over).

edit: and I found that missing axolotl. With difficulty. It seems like he really is just very very sneaky.