Cladophora ball "Aegagropila linnae"

A marimo ball is a rare growth form of algae, which grows into large green balls with a soft, velvety appearance.they are native to japan where they naturally grow at Lake Akan. They are also found in Iceland ,Estonia and scotland. They can grow patches on a lake floor at depths from 2 to 2.5 m. The round shape of the marimo is maintained by wave action that turns it.
In Japan the marimo has said to be a national treasure.
They where named by the Japanese botanist "Tatsuhiko Kawakami". Mari means bouncy ball and Mo is a term for plants that grow in water. So , marimo means bouncy plant.People often mistake them for living animals because they are usually moving around in the tank.
I first saw marimo balls when i was looking for an aquarium, then I immediately wanted them!

how to grow marimo balls

Your marimo friends will grow in tap water at room temperature as long as the water is changed every one or two weeks.
The growth rate of Marimo is about 5 mm per year.they grow particularly large, up to 20–30 cm (8–12 inches).

All they need is normal household lighting for them to make food, otherwise, indirect sunlight is fine.
You should turn them over once in a while for them to keep their round shape.
Marimo's are actually VERY easy to take care of, probably one of the easiest plants that live in water.
you just have to change the water once a week and your done!" make sure NOT to have age killer in the water!!!!"
1* They  do not float unless the water is squeezed out of them.
2* They are NOT moss, they are a very unique type of ALGAE.


Unlike the idea that they need little light,  they do best with lamp light especially if you have smaller, rolled marimo.
if so, they will start to grow outward like they do naturally and look very fuzzy.
They do still grow with little light but if you want fuzzy, healthy ones they need light.
[see pic]

Health problems:
If your marimo turns grey then simply flip it over and make sure the grey area gets light.
If that doesn't not work then you can get a bowl, add water, ice and salt, let them soak in that for about 3 hours .

they are a VERY easy plant ( ALGAE) to take care of and are nice for people that want a plant but don't have the time to take  care of it.
They are also a helpfull addition to to fish tanks, thus they act like miniature filters cleaning out the water.

i now have a website!  here:
you can visit "marimo in a bottle"my etsy store where i sell marimo's and their habitats.

please ask any questions!

1-40 of 41Next »
craftraptor1 month ago
Nice! I love marimos and I've always wanted one. Gonna go order some now :)
mmx29 months ago

Hey, i found something round sticking on my marimo's hair, and when I try to take it out i accidentally plucked marimo's hair, I heard from someone that plucking marimo's hair will break their structure, what should I do?

Marimo71 year ago
Hello, Marimos look interesting to me and I want to get one. I've read that they need to be bathed but I don't know how. Also, do they need to be fed? Please help. Thanks.
Hi! I have some marimo and they turn red all over the outside... Did it ever happen to yours? Do you know why? I can't find nothing anywhere in the internet...Thanks, Marcella.
Hi, I was wondering how long Marimo moss balls live out of water? I plan to buy my boyfriend some for Christmas in a mini terrarium, but I don't know how early to order them as I don't want them to die before I give them to him! Thank you :)
Serrot1 year ago
Hi, have 5 marimos and 1 month ago they stop to bubbling at all, they are green and normal the only difference is they are not bubbling like before, what happen with my marimos? thanks
neetz (author)  Serrot1 year ago
no need to worry! it is just because they have absorbed all the water they can and there are no more bubbles:)
tcalvs1 year ago
Question will Neutral Regulator by Seachem hurt my Marimo Ball? My ph is too low and I am trying to raise it.
Aqua lover1 year ago
Hello, thank you for all this wonderful info on Japanese mossballs. I was delighted to find them at the pet store and bought two for my 29 gallon freshwater tank. However our fishes loves to nibble on them and it causes a lot of the flying pieces from the mossball to float around which is making my tank look dirty. I'm a bit bummed out about and placed them in a separate bowl. Is there anything I can do about this? Thank you.
Luviana1 year ago
When I put the marimo on my table, there were a lot of ants, why?
Luviana1 year ago
I have a question. I live in Malaysia so it is always hot. Where do I put my Marimo ball? Does it need air?
neetz (author)  Luviana1 year ago
if it gets over 80 degrees just put it in a cool dark spot,
also, they do not need air:)
ssaeko1 year ago
Hello :3 I just got a moss ball yesterday as a birthday present. And I really want to take very good care of him. So I have questions to ask. So you can keep them in a jar with the lid on and they will be fine? They don't need air? And if I want more of them without hurting him? Like do they have babies? Like one day ill see a bunch of tiny babies next to it? And they will be fine if Iput them on a window where they will get direct sunlight for most of the morning or is that too much sunlight? Because I live down in texas where it gets really hot. I really want to take good care of my moss ball and make him big, fat, and happy. :3 so can you please help me? :C
neetz (author)  ssaeko1 year ago
I will answer all of your questions!
they do not need air, so a jar with a lid is fine:)
they eventually break apart, forming two marimo or little baby marimo will start to form off of them.
sunlight is fine, one thing people don't usually realize is that they are algae and grow LOTS faster in warm sunny water!!
just make sure to take it out of the sunlight when it it gets over 80 degrees.

please feel free to ask any questions!!!
you can lookat my etsy store :



sheri141 year ago
I have a question please, just bought a Marimo ball.. I keep getting white foamy bubbles that I think may be an algae bloom, My 25 gallon freshwater tank only has two Tetras left but because of favorable conditions for Malawi Cichlids I plan to change over to the African Cichlids, will the Marimo ball be ok for the Cichlids?
neetz (author)  sheri141 year ago
I do quite like Cichlids! I think they would do fine with them!
the fish really don't " eat" them if that is what you are worried about:)
they normally just push it around.
I have a plecostomus that I thought would eat it but he likes to play with it!

you can post a pic of the white bubbles if you would like!

please feel free to ask as many questions as you want!!!
jamob1 year ago
I was planning on getting one and saw at the pet store it was on a string floating upward, I know it floats when you squeeze water out but wouldn't it permeate through again and sink?
Thank you for replying, it helped ! :D but, in the parcel, wouldn't it recieve no light ??(I'm sorry, i couldn't reply to previous post for whatever reasons..)
neetz (author)  Ichigolicioux1 year ago
It would not receive any light but it would not die.

thanks again!

Hello ! This post was really helpful, thank you. I would like to ask, how doyou ship these marimos to other countries ? By parcel? And, is it fine if i add ice to the water? (The weather here is pretty hot. It is usually ~30°c D:) and what can i do if the marimos turn brown? Thanks in advance!
neetz (author)  Ichigolicioux1 year ago
Hello, thanks! yes, I ship by parcel.
you can add ice to the water, especially if it is hot where you live.
if your marimo turns brown, it is usually from a lack of light.
just turn it over so the brown side if up, it should turn green in no time!

thanks again!:)
please tell me if you have any more questions!
neetz (author)  Ichigolicioux1 year ago
Hello, thanks! yes, I ship by parcel.
you can add ice to the water, especially if it is hot where you live.
if your marimo turns brown, it is usually from a lack of light.
just turn it over so the black side if up, it should turn green in no time!

thanks again!:)
please tell me if you have any more questions!
hope1231 year ago
Is my Marimo having problem as it look like cover by a greyish layer.
If yes, are there way I can do to save it?
neetz (author)  hope1231 year ago
First, could you post a pic of it?
I might be able to tell what it is easier if I can see it

There are a couple of reasons why it is grey.
First, it could be just dirt/stuff from the bottom of the tank.
Try washing it gently a couple of times , see if it does not come off.
It not here are a few things you can try:

Method 1: try putting it in salt water and letting it soak for a couple of hours.
Method 2: try taking it and putting it in light, grey side up.
you can try one/ both of these.

Hope this helps!

Please feel free to ask any more questions! :)
ltan101 year ago
That's great to hear! I'm a bit paranoid and had been looking at the every few minutes. I feel like they are shrinking though. Is that possible? I have been keeping them in my lab (I'm a Master student in Japan) and leaving them overnight.
neetz (author)  ltan101 year ago
i have not heard about them shrinking, maybe it is from squeezing the water out?
ltan101 year ago
Hi, I just bought my Marimo recently. They are place inside a bottle with a cap. Should I remove the cap off? Also, I notice that some of the green fibers are floating around the bottle already. Is my Marimo in poor health (they are also not floating)?
neetz (author)  ltan101 year ago
your marimo are fine! they give off the fibers naturally, mine do that like crazy!
you can keep the cap on as long as you change the water at least once a week.
for them not floating,the truth is that they will usually only float if the water has been squeezed out of them.
your marimo would be brown-yellowish it it was not in good health.

please feel free to ask any more questions!:)
cchapman71 year ago
My daughter is doing a year of university in China where they are apparently quite popular. She just had one shipped to me from Japan.There were no instructions so thanks for the info!
neetz (author)  cchapman71 year ago
no problem!
hello I have 5 mini marimo balls and 3 bigger one, I just bought them, but I really like them already! in few months I have to go in Italy and I need to bring them with me... how can I bring them? will they be upset if I made them fly twice a year?
thanks, marcella
and how frequently do they reproduce themselves?
do you divided them in pieces or you let them divided by themselves?
neetz (author)  marcellahella2 years ago
Hello, I think they would be fine to fly many times a year!
I would put them in a plastic bag with a little water and use a rubber band to keep it closed while there are flying and just put them in an empty jar with water while not.
I do divide mine and roll them so they are in a ball don't have to, ,however, they don't split in half very often but they are very hearty plants!
thanks for your interest!
if you have any more questions just ask!
thanks for the help!
10stjsa2 years ago
Do I need to have a big aquarim our a small aqarim, I have a small aquarim. My Marimo is as big as your 2sec photo. And my Marimo dosent have alot of space in it. Do I need to have alot of space?
neetz (author)  10stjsa2 years ago
nope, they do not!
crossfire2 years ago
I loved it, they're so interesting! I may buy one from your site, they look pretty cool!
What's the rate of the babies coming out? this isn't like tribbles where they will take over my house is it? :P
neetz (author)  crossfire2 years ago
nope , they only have little ones sometimes. they won't have more then 5.

ChrysN2 years ago
Cool, that is very helpful. If you grow them in a bottle instead of an aquarium do you need a lid on it or does the lid need to be off?
neetz (author)  ChrysN2 years ago
it does not matter, just as long as the water does not spill out.
1-40 of 41Next »