Episode: 3825
Title: HPR3825: Creating a natural aquarium
Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr3825/hpr3825.mp3
Transcribed: 2025-10-25 06:01:58

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This is Hacker Public Radio Episode 3825 for Friday the 31st of March 2023.
Today's show is entitled Creating a Natural Aquarium.
It is hosted by Minix and is about 39 minutes long.
It carries a clean flag.
The summary is, setting up your first natural, self-sustaining freshwater aquarium.
Hello, this is Minix and I thought I'd give a little overview of how to go about creating
a natural aquarium, I call it natural because you're not really building an aquarium so
much as you are creating a self-sustaining ecosystem.
So you're emulating what's already existing in nature just in a glass box in your own
home.
About me and aquariums, I've probably been doing this for about 25 years now, but I didn't
get into the natural side of aquariums until, say, 2015 or 2016, so maybe six or seven
years.
And I really wish I had done this from the beginning, I started out like most people do,
just a regular rim aquarium with candy-colored pebbles in the bottom and the plastic plants
and the little castles and some guppies or mollies and a little pleco and just did my best
to keep everything alive.
And I did that for many years.
I kind of graduated to pebbles in the bottom, like stones and then more elaborate decorations
and things like that, but basically it was the same concept.
Everything was pretty much artificial, every once in a while my fish would get sick and
I'd have to put the sick fish in quarantine so it wouldn't spread out through the rest
of the tank and then I'd do water changes once a week or every two weeks and so basically
it was just the box to watch fish swim around, not much else going on in there.
But about six or seven years ago I started this method of natural aquariums where I worked
on creating something that would be more self-sustaining and fish would not get sick, the aquarium
itself would kind of regulate itself, it would be balanced and it wouldn't have to do water
changes anymore and just a lot of positives compared to how it had been doing it.
So I'll just preface this by saying that if you're going to get into this whole natural
aquarium type of hobby, it takes a lot of patience and there's no really quick fix to anything.
If you just want to get up and start it right away, this probably isn't for you, but
if you are into a challenge and something that's really pretty to look at and something
that's kind of holistic in your approach to it where everything works together and you
may be interested in this. The best way to start is with the aquarium itself. If you're
new to aquarium and fish in general, I suggest a larger aquarium if you have room for it,
at least to 20 gallon. This is because the bigger the aquarium, if something goes wrong,
say there's a big nitrate spike or ammonia gets out of hand or something like that, usually
it's easier to catch it before it crashes your tank just because you have more water volume
to work with and as you test the water, you can kind of see a slower rise in bad pollutants
where if you have a smaller tank, a tin or eight or five gallon tank, if something gets out of hand,
it does it really quickly and there's a big chance that your whole tank will crash and you'll
have to start over. So if you can and you just get to start, I suggest a 20 gallon
if you don't have room for it, you can do a 15 or a 10 gallon. I wouldn't go below that if
you're new to the hobby because unlike some things, the smaller it gets, the more difficult it can be
as far as managing things because water chemistry changes happen so quickly in smaller volumes of water
that you can be frustrated and just decide to quit altogether. So aquariums themselves are just
glass boxes. You can find good deals on them, certain times of the year at places like Pets Mart
or Petco, they'll have the dollar gallon sale or you can get a nice 20 gallon for $20 and
if you don't want to buy a new, you can always buy used, lots of places, Craigslist, Facebook Marketplace,
places like that, people are getting rid of aquariums all the time. The only issue is make sure you
have a chance to test the aquarium. In other words, fill it with water before you actually buy it
because sometimes older aquariums can leak and if you're not used to resealing aquariums,
then you may just be out your money. So if you have a chance to test it before buying it,
if you buy used and it's not from a store, then I would recommend doing that. Otherwise,
that's all you really need. There's lots of different kinds of aquariums, but if you're just
getting started, I recommend not spending that much money because you don't really know if you're
going to like this hobby or not until you start to get into it and see if you have the patience for
it. So say you have a, you've bought a 20 gallon aquarium to have rimmed and rimless
rimmed aquariums or your standard aquarium you see with just a black plastic rim on the top.
Rimless don't have that. They usually have thicker glass to compensate and better sealing so
that the walls of the aquarium don't fall apart, but they don't need that plastic rim, but usually
they're more expensive too, just because of the quality of the glass. If you do buy a rimed aquarium
that has the plastic rim, be aware that any kind of filters you put on the aquarium or lights
may not be able to fit it. Some will and some won't, they'll tell you, but if you have a filter or
a light already you want to use, it's very easy to cut away the plastic rim and the spot that you
want to put the light or the filter just so it'll fit on the glass and it's not really a big deal.
But otherwise, just start with the basic aquarium. Next you want to go to substrate, which is what
you're going to put in the bottom of the aquarium. The easiest and cheapest way to do it,
which I also think is probably the best way, is just to use regular organic potting soil.
You can find this in any like a loaves or a home depot, any hardware store, a gardening center,
anything like that. You want to make sure it's organic because you don't want chemicals in there
that are going to leach out into your aquarium and arm your fish or your livestock and you can
just get a small bag of that and then get some sand. Pull filter sand is what I like. It tends to
have, sorry, I've done more as my cats gone crazy. Pull filter sand has the grain size that I really
like and it's really cheap. You can buy a pretty big bag of it for pretty cheap. So what you want
to do is put, say it's a standard 20-gown aquarium, you put about an inch of the potting soil on
on first and then on top of that you want to put two inches of sand. You want to keep your ratio
about two to one for sand to soil and that should give you thick enough sandcap so that the soil
number one doesn't leach out into your aquarium and number two it gives you a layer that
becomes anoxic which means it doesn't have any oxygen. What you want to cultivate a certain type
of bacteria that helps to break down fish waste and fish food and mom and just general waste that
settles to the bottom of the tank. The sand is good because even though it can create a cap
to give you that anoxic environment at the bottom of your tank, it also is kind of
shaped in a way that the waste that falls to the bottom of the tank or the food or whatever
eventually settles through the sand into the soil. So it's not completely impermeable
but once you get deep enough into the soil then it is. So the sand gives the waste time to
break down and then settle between the grains and go into the soil and break down the bacteria.
So you've got your soil and your sand. By the way you can go with a gravel bottom if you want but
I recommend if you're going to use gravel to use a planted aquarium type of gravel there's
several kinds and they're usually all volcanic in nature and so usually they have tiny little
micro holes and they're somewhat porous and what this does is give surface area for bacteria to
colonize because most of your bacteria is going to be on surfaces when they're new aquarium
rather than in the water column itself. So if you decide to go the gravel route make sure
your layer of gravel is thick enough so that eventually when you get to the bottom of the gravel
that you'll have that anoxic environment but also make sure it's the volcanic type of gravel
or volcanic soil sometimes they call it. There's a few different brands you can just look up a
planted aquarium gravel or planted aquarium substrate and find those pretty easily at your
pet store on Amazon but a cheaper and in my mind better way to go about it is just to do the soil
and the sand. So that's your substrate once you get that in you'll want to add your water.
Now this kind of depends on where you're located. Some smaller towns and cities
have just chlorine in their water which is not a big deal. You can just pour your water into
a bucket and let it sit out a couple of days and the chlorine evaporates but a lot of larger cities
have moved to chloramine instead of chlorine which does not evaporate from water. So you need to
add a declorinator which is not a big deal. Usually like a cap or a half cap full
to every five or 10 gallons it'll tell you the directions on the bottle and where I live we have
chloramine in our water so I use the declorinator and just with regular cap water I don't add
anything else to it and it's almost instantaneous how fast the chlorine is eliminated from the water
so I always have like a two and a half gallon to a five gallon jug full of water that I've treated
so I can top off the tank when needed. So to add the water to your tank and if you have well water
you don't have to worry about any of this. Actually well water is really nice for natural
aquariums because of the carbon it's the TDS is good for the plants so they need to let those
minerals and things like that so I recommend putting some kind of bowl or a dish in your aquarium
and the bottom on top of the sand before you pour the water in and just pour the water on top of
that and that keeps you from penetrating the sand bed and having the soil each out into your water
and just pour it slowly about three quarters up to the top of the tank so that you still have room
to put your hands in there and maneuver around and stuff so that's the substrate that I would
recommend for a natural aquarium. The third step would be to get you some plants most large
pet stores or fish specialty stores where I have plants and stock and you can talk to the shopkeeper
or the employee about what kind of plants are good for our beginner. I recommend stuff like
oh perlweed or herbicopa or lewigia or some of those are the easier plants to grow and you're
just starting out. You want to kind of stay away from the higher end plants that are like
Monte Carlo which is a carpenting plant or baby tiers. These tend to take CO2
which is more of a high tank or a high-tech type of tank where you infuse CO2 into the water
and usually use an inline diffuser with a canister filter and it's a lot more expensive
so if you're not sure if this is a hobby for you or not I recommend kind of going low tech with
just the easy to grow plants and they're pretty easy to plant into the sand once you get the hang
of it the easiest way is you just use a long pair of tweezers and grab the bottom of the stem and
and just kind of push it into the sand but you don't want to go all the way into the soil
just into the sand and the roots will eventually find the soil by themselves. You just don't want
to risk piercing that sand cap you got on top so that's one way you can do it another way is if
you happen to live by a river or creek or a nice pond you can find plants there as well and the
thing about natural aquariums is they are made up of a very diverse ecosystem so there's
all kinds of bacteria you want in there there's all kinds of microphono which is like
arthropods and scuds and and just tiny little water bugs and things like that this is going to be
part of your cleanup crew so there's no harm in getting plants from from from ponds or creeks
or things like that if you if you're lucky enough to have those sources close to you and just
putting them in your tank now they may grow and they may not if they don't grow that's fine you
just pull them out but if if you don't have those sources there's nothing wrong from getting them
from a from a pet store or an aquarium store like that and just you want to really fill up your
tank with plants early on you may have issues with algae and the more plants you have in your tank
the more competition here is for algae so algae will grow in the beginning especially
before the plants get established before they root and actually start taking in nutrients
just because you don't have any competition for the algae so the more plants you can fit into
tank the better and the better it's going to oxygenate your water and and things like that
so once you got your plants in the tank just arrange them how you like I like to group
plants together that are the same species it just looks a little nicer and it kind of gives
your fish different environments to go towards once they're in the tank but you can do it however
you want however it looks nice to you they also have floating plants which are nice
that just float along the top and they take nutrients out of the water too and keep your
water clean you some of those are like a frog bit or red root floaters or one thing I would
recommend by staying away from is duckweed which is a really good plant as far as growing fast
and reproducing but if you don't like the look of the tiny little leaves it can be really hard to
get rid of so if you're absolutely sure that you want duckweed go ahead and get it look at some
pictures on the internet if you like that look I just know that you'll be pulling out handfuls
of it as your tank progresses are quite often because the growth is really fast
and it can shade out the rest of your plants to keep the light from reaching your plants
so once you got your plants in there you got your water you got your substrate
one thing I like to do to get the tank started even if you didn't get your plants from a pond
or a river is to go to a natural body of water and just kind of reach your hand in there and get
some old leaves and a little bit of mud and put them in a container and bring them back to your
place and and just put it in your tank and this gives you a head start on giving you the type of
bacteria and biofilm and things like that and microfond I like the little insects and water bugs
that you need in your tank to complete the ecosystem this will be part of your cleanup crew
and part of your biofilter so the way we'll be doing the tank is we'll be creating as
diverse and as large a biofilter as we can what's your biofilter consists of is mainly bacteria
that converts things like waste matter and and old food and things like that into the the
building blocks that your plants need like the nitrates and and things like that like your
your your plants are not going to grow well unless they have the nutrients they need
and the bacteria is what converts these these waste products in a nutrients for your plants so
that's going to give you a head start as far as getting a a diverse colony of bacteria in there
what happens when you have a completely kind of sterile type of tank where you have just the
plastic pebbles and and and you know you're putting chemicals and stuff a lot of times you'll have
a monoculture of bacteria in there we'll just one type of bacteria takes over and a lot of times
it's not the kind of bacteria you want and what happens is your fish gets sick and you can't
figure out why and usually it's because the the bacteria you have in there is not the right kind
to recycle nitrites and to nitrates and things like that so the more diverse colony of bacteria you
can get into your tank the better so that's kind of the the the secret ingredient to building a
natural tank is is to seed it from a water source elsewhere by putting in some old leaves and
and things like that the bacteria and the microphone it will be on already so after you after you do
that I like to let my tanks cycle for a while some people say you don't need to cycle tanks I find
I find I have much better luck when I when I let the bacteria start to grow and colonize
and then tank and during this process you may see a white cloud which is which is the bacteria which
is fine you don't have to do anything it'll go away on its own but but you just let that bacteria
begin to colonize your tank you know start coating surfaces and you may see kind of a white film
and this is just biofilm which is made of bacteria start to collect on things like rocks and wood
and whatever else you put in your tank and that's fine because you need that you need to coat
all the surfaces in your tank and to really do its job to act as a good biofilter so the longer
you can let that tank sit the better before you actually put livestock in there I like to let the
tank sit at least a month so like I said it takes patience to do this right and to have a tank
that will regenerate itself when it needs to heal itself when it needs to it's almost self-sustaining
after a while so that's kind of how I would do it I would just let it cycle but while it cycles
you can go ahead and add a filter to your tank my favorite kind is just a small sponge filter
these are very simple little devices it's just a usually a black or a green sponge around
a little plastic pole and it has a weight on the bottom so it sits at the bottom of your tank
and within a little plastic tube you insert an airline and that connects to an air pump that you
have outside your tank this is one of the oldest and simplest filters but to me it's one that's
still one of the best for natural tanks instead of the hang on the back filters or the elaborate
like filters that have the cycling media and it and stuff like that just a regular old sponge
filter is probably my favorite it does what it needs to do it it collects the tritus as you pump
air through it it pulls air inside as you pump air through it pulls water into the sponge itself
and that's how it actually filters the tank and but the best thing that I like about sponge
is these sponges have a large surface area compared to their size so all that good bacteria you
have in your tank is able to colonize that sponge filter and it has all this surface area in it
it's full of that will eventually fill with that that good bacteria you want that that says
your bio filter and sponge filters are probably about the cheapest you can buy it too you can find
them anywhere you know small ones for just a few dollars and air pump is pretty cheap too or between
five and ten dollars you can buy an air pump at Walmart usually or if you don't want to spin
pit store prices or whatever but either way you go that that that's kind of the type of filter
I would recommend would just be a small sponge filter and just let that cycle in your tank as well
while your whole tank is cycling and then after about a month the water should be nice and clear
and you should see no more sediment in the water and no more white clouds of bacteria and go ahead
and get a little water test kit you can buy either the little test strips which work fine or you can
get more more of the complex sets that use the vials and you add a reagent to the water and then
you can pair the color against the chart either one's fine but I find that just starting out you
probably won't want to spend too much money and you can buy a little bottle of the test strips
fairly cheaply and they'll tell you on the side of the bottle exactly what the colors mean on
the test strips and where you're at so when you're when you're ready for fish you don't want any
ammonia in the water you don't want any nitrites in the water you do want some nitrates nitrates
is what's actually be feeding your plants but it doesn't you want to keep it between 10 to 20 ppm
usually and usually the colors on the test strip will give you that approximation so you test
a water and if everything looks good then you're ready for your fish and you're ready for your
lights now the lights are one of the few things I would say that you really don't want to
scrimp on because you want a really nice bright light but you don't want it to be hot either you
don't want it to heat up the water you want it to just be bright enough so that your plants will
grow and they'll take in nutrients and they'll clean your water column and oxygenate the water
for the for the livestock there's so many different brands of water I mean so many different
brands of lights now that you could just take your pick but to get a good good set of lights for
a 20 gallon expect to spend between 30 to 50 dollars starting out with and they can get much
more expensive than that so but that's one thing I recommend actually spending money on because
it's gonna pay off in the long run a good light will last longer and your plants will grow better
now while your tank is cycling you don't need lights or else you're just gonna grow a bunch of
algae so but in the meantime you're gonna you're not gonna have any lights it's just gonna run on
it's on its own and the bacteria is gonna populate but as soon as you put those plants in there
uh that's when you're gonna want the lights to come on so uh so if you if you want to just cycle
the tank uh for about a month with no lights make sure you don't have any plants in there because
have they're not gonna grow they're gonna die without light but uh anyway so get you a good light
or a set of lights uh and then you're you're ready to go you have your natural aquarium now
now what you want to look for before you put your fish in you want to make sure you have
uh you know you tested your water and you want to look at the sand carefully and see that your
microfarmer has already been breeding the little tiny bugs and things like that because that's
gonna be part of your cleanup crew uh that along with snails usually and uh and and and maybe
a little bit of algae don't get freaked out by algae uh some people do as long as it's not overtaking
your tank it's okay uh algae is also a part of your uh your ecosystem so as long as not covering
your plant leaves the point where they can't get light uh you're okay uh algae I've always
looked at algae and in snails as well as kind of the canary in the coal mine which is kind of an
indicator of how your tank is doing uh people get freaked out when they see snails in their tank
because they say they're ugly and things like that but snails in your tank are good that's part of
your cleanup crew as well that the snails and the little microfarmer and the bacteria they all
they all eat the the dead food and the fish food and the wasted food and things like that
and they're able to process it for the bacteria which process it further and gives food for your
plants so um that's kind of what you want to look for is make sure your microfarmer is populated
make sure your plants are looking nice and healthy and once that's done you can your water looks
good you put your fish in now as far as fish goes that that would be a whole another
a whole another episode because there's so much that goes into it uh pick fish that you think
you would like to see then you know because this is not just an ecosystem but it's something it's a
decoration it's something that you want to uh take joy and and just watching and kind of show off
to people so i like i like the little small nano fish like rest boars or danios or
or things like that but you can you could add any type of fish you want it as long as you know
what it takes to take care of the fish um i have a few specialty fish that take a little more
care and and and use some of them even take live food and things like that but uh usually you can't
go wrong with the some rest boars or or things like that uh copies and mollies are okay uh they tend
to be a little dirtier and um they tend to poop a lot more and so i i like to go with some of the
the smaller fish when it comes to first starting a uh a tank i use a recommend really small fish
to people that are just getting started and also because these small fish can usually snack on
microphone that you've already got started in your tank so uh that's that's pretty much it
uh it just i would just put a recommendation out there that uh if you're not a patient person this
is probably not the hobby for you uh because this a good self-sustaining tank to get to that point
towards just cruising along and you don't really need to do much else as far as besides just
trimming the plants when they get too tall or uh things like that uh usually takes
aim for where between four to six months somewhat sometimes longer uh after a year your tank
should definitely be stable enough if you're doing everything right to to kind of be self-sustaining
and by that point uh the water should always be nice and clean and nitrates should be uh pretty
minimal and and you won't have to do water changes anymore because the tank kind of takes care of
itself you have your own self-contained little environment natural environment ecosystem going
there and all you'll have to do is just top it off i never do water changes anymore not have salt
water tanks that i have to do water changes but that's just to add and um you know all the minerals
and stuff that the coral need but as far as fresh water goes you really shouldn't have to supplement
anything and you shouldn't have to do anything water changes once your once your tank is cruising
along then the beginning you may want to do a few water changes just to clear it up a little bit
and to get your uh parameters where they need to be but after a while when your plant plants are
growing and the purling went really well which means they're producing oxygen uh it produces
these little pearl-like bubbles on them and there's not not much else you have to do which is why
one of the big advantages of these natural type of aquariums is that uh they are pretty much
self-sustaining other than feeding the fish and topping off the water uh usually if you have enough
snails and a cleanup crew you don't even have to clean the glass they kind of take care of that
as well uh so so snails and algae are not really anything to worry about unless they get out of hand
to when you start to see a lot of snails you know that you're overfeeding your fish a good rule of
thumb with fish is just feed them what they need not what they want because fish are always hungry
they'll just keep eating and eating and eating even though they don't need to uh the only one
to keep you know feed them enough to stay healthy and as long as your fish are swimming around and
they're not laying on the bottom and and they're pretty active and they're they're plenty healthy uh
I feed my fish uh my you know non-specialty fish maybe twice a week sometimes sometimes
with third time on the weekend but not often and very little food uh just enough to take
and eat in one session uh have a tank with some um chili respores in it which are these tiny red
nano fish and I just uh just put a tiny pinch of food on the top of the water and as it sinks into
the water column they snack it all up and it's usually gone by the time it hits the bottom before
it even you know has time to hit the bottom and that that's kind of what you want to look for when
you're feeding your fish so if you if you're feeding properly you shouldn't have an issue with
snails if you see a lot of snails you know you're overfeeding if you have a lot of algae it could be
a few things it could be overfeeding as well uh it could be not having enough plants in your tank
because the plants provide competition for the algae and usually keep the algae at bay or it could
be that your lights are on too long I usually keep my lights on between eight to ten hours depending
on how the tank's doing if the tank is susceptible to algae uh I'll shorten the lighting period to maybe
six and a half seven hours but uh once once your plants are really booming and growing well
you can crank that light up and and they should keep the algae at bay it should be enough competition
to keep the algae at bay so uh my I have a a little six gallon that I keep the light on for about
ten hours and those plants go crazy and they love it and I don't have any other problems at all
so look for algae and snails to be your friends and not not to be something you're you're constantly
battling because those are really good to have in your tank and also they they provide a natural
barrier against your tank crashing if all of a sudden something goes wrong there'd be a fish die
that you didn't see and and now you got this big ammonia spike in your tank and instead of
your tank is crashing the algae will actually start to bloom but it absorbs all that ammonia that
comes from the dead fish and it keeps your whole tank from crashing snails as well snails if
you're overfeeding they they'll eat the food and they'll keep uh keep the ammonia from rising
in the in the tank and and and it's kind of a natural way to keep your tank in check so what
you really were creating here is a whole ecosystem that works together remember you've got all
these variables you've got your water you've got the substrate that's doing its job with the bacteria
you have your little microfana that are breaking down food left over food and and fish poop and all
that you got to remember when you feed your fish that food gets eaten seven eight nine ten times
before it actually gets to your plants because you're you're fish eat the food and then they poop
it out and then the snails eat the food and maybe if you have some small algae eaters like out of
St. Cluster what some some of those they will eat the the poop as well and all all these critters
in your tank the microfano will eat it and and that food gets eaten several times before it even
makes its way to the plants and then they get every little bit of protein things like that out of the
food which is good for your for your tank because you don't want that stuff sitting around in there
so the the larger and more diverse cleanup crew is what I call them of snails and microfana and
bacteria you can build up in your tank you're going to have a lot easier time with it and you're
going to you're going to have a lot less frustration so remember that this type of aquaculture or this
type of aquarium is is meant to be very diverse it's going to be a little dirty it's not going to be
look clean and sterile like what you would see in a doctor's office but it's going to be a lot
healthier too you're not going to notice you're fish getting sick like they would in a sterile
plastic environment because they have what they need to stay healthy and survive and they have
plenty of oxygen from the plants they don't have pollutants in the water from rotting food and
things like that and and they got what they need to have a nice slime coat on their bodies and
and things like that so there's some different definite benefits to this this way of keeping
an aquarium you know and there's some negatives too like it's it's a lot harder to keep it balanced
in the beginning because you're you're constantly checking things and and maybe you're not feeding
I mean maybe you're feeding too much or are all kinds of variables but that's what those test
trips are for those kind of tells you and also you know just watch what's going on in your tank and
and after a while you'll find it just kind of cruises along on its own and you don't really need
to do much and it becomes a lot more enjoyable so so think about it think about starting a natural
aquarium and if you're into gardening or if you if you're into environmentalism maybe this
would be a nice little or hobby for you because you get to really see how this kind of ecology
evolves over time and works together and everything that kind of comes together the way it should
just like it does in nature so hopefully this will give you kind of a spark of interest
maybe to try this on your own I'd really like to hear from people that they do this or if you're
just getting started feel free to ask me questions or getting in contact with me I am Minix and I am
usually on the Linux lugcast the first and third Fridays of the month you can go to Linux
lugcast.com and you can find out how to join the show if you like we'd love to have people come on
and join the show I just want to ask me questions you that you can find me I'm master dom I'm at
Minix am I in and I X at up all night dot minix dot dev and I post pictures of my aquariums and
sometimes of my cat and things like that but I'd be happy to answer any questions you might have
about this hobby up and doing it for a little while now and I really enjoy it and I really enjoy
helping people too so anyway that's it for now and I hope to see you on the other side
tonight. You have been listening to Hacker Public Radio at Hacker Public Radio does work. Today's
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