Housing 3 Male Betta Fish in 1 Ten Gallon Tank




About: I usually end up doing an instructable because I have to figure out how to do something myself. I just get pictures during the process, and if it works out, BOOM, an instructable!

** Disclaimer: **

Please use caution when dealing with male bettas.
Do not put them in an undivided tank, or they will kill each other.
Always use care and common sense when dealing with your fish.

You may have bettas that are just the opposite of mine. This method, and the information contained in this instructable, is from my personal experience and online research.
I take most online information with a grain of salt, except for the information on Instructables, of course !

Here's a quick example: Online, I read that bettas do not like currents, since they live in puddles in their native habitat. This rules out the use of most filter units that work well.

My experience: I turned on the filter, which makes a current, and the betta investigated it, swam around in the current, and had no problems.
I keep it on the lowest setting, but still, all 3 fish have been in with the filter, and after a 30 second initial investigation, they have no problems with the filter or the current.

**** BACKSTORY ****

Well, I had a betta in the past, but one day he got his feeler caught in the marble-shaped glass beads on the bottom, pulled part of it off, got an infection and died.
He was a great fish, with lots of character (for a fish).

After that, it was about 5 years before I tried again. My girlfriend and I were shopping when we found 3 (yes THREE) betta fish. We couldn't decide which one we liked best, so we bought all of them, and housed each one in a separate glass vase.

Fish #1 (sail) and Fish #2 (poof) were in 1 gallon vases, and Fish #3 (shadow) ended up in the former betta's 2 gallon vase.

**** WARNINGS ****

I know that a lot of people say that these fish don't need a filter, swimming space, food,
and all kinds of other crazy stuff.
They may be able to live in a very small jar with no filter, but is that healthy for them ?
Do they like it ?

I say ======> NO !

The plant idea is also junk. These fish are meat eaters, and at some point they will nibble at the plant's roots when they are starving. The betta in a jar with a plant and no food is a BAD idea.

You have to maintain the roots and leaves of the plant to keep from having dead roots in the water, and you still have to feed the betta !

**** Back to the BACKSTORY ****

Long story short, it became a major pain to clean all 3 vases every 2 weeks. I tried a little filter that worked on the movement of air to draw water through the filter. It didn't really do much, except amuse the fish, and if you moved the filter (to clean it) it would release all kinds of junk back into the vase.

So I hit craigslist and purchased a 10 gallon aquarium with a stand and light for $15.
What a deal !

I had already seen aquarium dividers at the pet store, so I was ready.

Well, I thought I was ready !

Step 1: Buy the Components and Set Up the Aquarium.

I cleaned the aquarium and rinsed it thoroughly. Then we headed to the pet store to pick
up the dividers (I needed 2)

When we arrived at the pet store and examined the dividers more closely, we realized that they were clear.
If you're not familiar with bettas, then let me explain.

If they can see each other they get very aggressive and try to attack each other.

I asked the guy that was working at the (commercially owned pet store name here)
if there would be a problem with the dividers being clear.

He said 'absolutely not'.

He went on to inform me that after a few hours of seeing each other, the fish would calm down and there would be no real problems.

Not fully satisfied, I purchased the dividers anyway, and some small aquarium gravel,
(NEVER use the glass flat marble rocks - unless you want a dead fish) then headed home.

** These instructions come with the divider **

The setup was pretty simple. Trim the divider panels to fit, put the side channels on the divider panels, fit the stabilizer channels on the top and bottom, slip the entire assembly into the tank, then fit the clips over the outside of the tank and down into the channels to hold the panels in place.

The illustration shows you sliding the divider panel down into the channels, but the material is too flexible to do it that way.

Once the dividers were installed, we put the gravel in, then the plants,
and then (slowly), the water.
After about half the water was in I put the recommended water treatment in, then finished filling the tank.

Then I installed the filter, an Aquaclear power filter 20. It was the smallest one that seemed to have the best multi stage filter.

Step 2: Adding the Bettas...

Once the tank was ready, I put each betta into his compartment.
The tank measured 20" wide, 12" top to bottom, and 10" front to back.

I made the center area 7", a little larger than the side areas (6.5"), so that the filter
would have plenty of room.

This was a serious upgrade in size and water quality for the bettas !
10 filtered gallons vs. about 4 unfiltered gallons (between the 3 vases).

After all 3 were transferred, they could see each other, and started getting mad.
I couldn't get a good picture because the dividers are clear, and the fish were very angry and swimming around very fast.

They couldn't get to each other, so I left the light off and kept the room fairly dim to see if they would get used to each other.

The next day I called every aquarium shop and pet store that I could find, and they all only
had the clear dividers.

This may work for other fish, but not for male bettas !

After 2 days, they were all the same. Mad, tired, mad, tired.....
It looked like the clear divider material wasn't going to work out.

I tried getting different types of material and drilling holes in it, but that was very time consuming.
First you have to find a thin rigid opaque plastic, drill tons of holes in it, then go back and smooth out the exit side of the drilled holes so that your fish don't get scratched up if they brush against the divider.
My experiments looked bad with just a few holes drilled, so I scrapped that idea.

After some thinking about materials with holes already in it, I came up with an idea that would solve my problem !

Step 3: The Solution to the Problem.

After going to all of the home improvement and pet stores in the area, I finally decided to use perforated vinyl siding. There were no other options that I could figure out in a timely manner.

I thought of the siding right away, but I was looking for an alternative.
I thought that vinyl siding would look bad, and I didn't want to buy a giant piece of it since I only needed about 2 feet of material.

There was some good news, though:

The siding fits easily in the channels that came with the divider set.
The vinyl siding has less holes than the clear plastic, but the holes are larger, and both sides are fairly smooth, so I didn't need to polish any of the holes to get rid of rough edges.
The siding is more rigid, so I didn't need to use the top and bottom stabilizer pieces that came with the original tank dividers, and it ended up looking much better than I thought it would.

The area of the vinyl siding with the holes in it was wider than 10", so
it was easy to cut out the size that I needed and keep plenty of holes for water circulation.

My finished pieces were about 9 3/4" wide, by 11" tall.

After I had the pieces cut, I made sure to clean them thoroughly with warm water while rubbing them down with a mild abrasive sponge. Then I rinsed them several times, also using the sponge.

Hopefully that removed any residue that may have been there from shipping and sitting in Home Depot.

I think that they can get a glimpse of each other once in awhile, but none of them have gone into full fighting posture since I installed the new vinyl dividers.

It turns out that the aquarium looks even better than the vases did. The flat pieces of glass
don't distort the image of the fish, and you can get fairly good pictures of them as well.

*** Success ! ***

Now there are 3 happy bettas, and 2 happy betta owners in the house !

Here is a picture update with some aquarium additions and matching style backgrounds. These fish are very inquisitive, and they love having something to look at.

*** UPDATE 3/15/2012 ***

I have decided to add the following information to the end of this instructable regarding PVC, which is what the soffit is made from, since my comment in the comment sections seems to get missed a lot!

Hey all, I just got an answer back from Owens-Corning, the makers of the siding that I used in this instructable: "I am writing you regarding your question around the possibility of vinyl leeching once it is exposed to water for long periods of time. The vinyl siding or soffit in this case by its nature of chemical bonds will not breakdown when exposed to water, or leech any materials used in the manufacturing of the vinyl. Once the materials used to manufacture vinyl are combined the bonds of the material can not be broken down, hence the reason vinyl is 100 percent recyclable. In fact vinyl is used as a liner and cap for many landfills because it is inert and stable."

The only time this material can be hazardous after its manufacture, as far as I know, is when it is burned, which would be difficult if it's in your fish tank!



    • Fandom Contest

      Fandom Contest
    • Beauty Tips Contest

      Beauty Tips Contest
    • Pets Challenge

      Pets Challenge

    96 Discussions


    2 years ago

    Welcome to 2017!

    Unlike some things on the internet, old instructables are still just as useful now as they were when they were written!

    I check in now and then to update things that may not be clear, and to reply to comments.

    I think it is so cruel to keep Bettas all alone! I have 23 male Bettas in a 55 gal community tank and in almost a year there has never been a sign of aggression! I started "adopting" them when I would walk by and see some dead or near death at Petco. They respect everyone's space and clearly love swimming in all that space and love their high quality frozen foods. They make me so happy knowing I probably rescued them from death and their gorgeous colors and flamboyant fins and tails brighten my day.

    3 replies

    Thanks for your reply! For Bettas sake I wish more aquarists would do it! If they didn't get along there wouldn't be males in nature!


    3 years ago on Introduction

    I have three female betta's in one 3.5 gallon tank (now learning that that's too small, and too few females?) Pecking order changes from time to time, and damaged fins and pulled scales are usually the result. I'm finding my main problem though is feeding fairly. My lil Fresca (once the smallest timid & scared girl, is now on the top of pecking order lol..you go girl!!) Gobbles the pellets as soon as they hit the water, but this food either seems to have clogged her up and put pressure on her swim bladder keeping her at the top of the water like a buoy, or she has dropsy which I really do not think that's the issue. Didn't have an issue with that before with the usual brand (Omega-1), but I was away, husband ran out of food and bought a different brand (Tetra, with color enhancers)..also floating, but for way too long and she'd get them before the others could. She was a tad ratty when I got her. The other two girls were going to be the only purchase but I felt bad for her, like no one would take her home and take good care of her...& she just looked plain sad. So yes, I caved and took her home :) Now she's the queen of the tank with a buoy for a belly :( At least she's still spunky though and holds her own. Guess who's getting a cooked pea tomorrow? lol I added a real plant last night for some added cover, along with a couple small plastic plants. Need those hiding spaces for flare ups to keep stress levels down.


    8 years ago on Step 3

    Anubis--This is a wonderful instructible. I'm happy that you upgraded your bettas. Having had bettas in the past, I can tech support one of your problems. When you moved them from their individual "puddles" they had been living in, and moved them into closer quarters, they began fighting over territory. In their homeland, they live in heavily planted areas that divides them up into natural territories of pockets of small pools of water. When you upgraded the size of their pools, you missed the critical step of upgrading the greenery that helps shield and define their territory. Bettas are actually happiest in a heavily planted aquarium. (Not under plants, but amongst them.) If you add things like Java Fern, water onion, certain types of lily, and many other very easy to grow aquatic plants that all live below the water line, not only will the fish be happier, and thus healthier, but it will also mean that your aquarium water is more stable, as the live plants help filter the water and also cut down on the growth of algae. Best of luck with your fishie friends.

    5 replies

    Excellent advice about their natural habitat. I have several friends who have kept 2-3 male bettas in various tanks from 20g-33g longs.

    I am going to attempt to do this with 2 in my 29 wide, and potentially 2 in my 20 long. People think I'm nuts when I tell them what I'm going to do, but once I explain to them that bettas do not live solo in their natural habitat & what I am doing is my best to recreate that natural habitat, they look a little less skeptical. It could be an act to shut me up, but whatever! Fish geeks unite!


    Reply 8 years ago on Step 3

    Thank you for the ideas! I'll see how the live plants go. I tried some earlier and ended up with a snail infestation!

    Snails are pretty much inevitable when you bring in live plants. The best way to get rid of them is using Assassin Snails. It's a little morbid, but such is life!


    Reply 5 years ago on Introduction

    Okay so snails, Shmails! If you rinse your new plants before putting them in the tank then you can rinse off any eggs or snails. Seems sad but it's better then them killing your fish! And your eggs will look like clear glue all together but they come off easily, Thankfully! Also if you ever buy anything off of kijiji make sure to always rinse it off and let it dry completely!! This will kill anything off that may have been there from the previous aquarium/Community. If you do by chance get snails, Then put a piece of lettuce or two overnight and when you wake take the lettuce (Which will be full of feasting snails) and pitch it. If that starts to not work then all you need to do is feed the perfect amount and then scoop out extra food. Good luck!


    Reply 5 years ago on Introduction

    This is one of those things that you usually find out after the fact..Hopefully the info will help others - it did not help my bettas, one specifically that was wolfing down the snails and died because of it.

    Hey :) nice instructable. I have some bettas in roughly 2 gallon tanks each, but I don't have a heater since it is usually warm where I live. This winter was a smidge too cold so I put them in my larger tetra tank in little containers during the night (when it's coldest) but they don't seem to have any problems seeing each other. Initially they flared up a bit, but after about an hour they stopped and never did again even when I separated them and put them back together. They did flare when I got a new betta tho...

    Hey :) nice instructable. I have some bettas in roughly 2 gallon tanks each, but I don't have a heater since it is usually warm where I live. This winter was a smidge too cold so I put them in my larger tetra tank in little containers during the night (when it's coldest) but they don't seem to have any problems seeing each other. Initially they flared up a bit, but after about an hour they stopped and never did again even when I separated them and put them back together. They did flare when I got a new betta tho...


    9 years ago on Step 3

      Okay. Here goes. I'm pretty new to Betta's. I ended up with one at a White Elephant Gift Exchange. LOL. I have 3 pet rats and so I tried to give it away (though I really wanted it), but couldn't. So, alas, with Christmas money I bought him a bigger tank, 5 gallons to be exact. It was the best tank I could find for a filter and light and had GREAT reviews for Betta's (I'm really obsessive about getting the best of best and all the correct information before I buy something).

     So anyways... I want another one. Haha. I got the Eclipse 5 Hexagon tank because I needed something that would fit in my room. I kinda wanted the standard rectangle they had in the same brand, but again, I needed something that was a space saver. So now I have this oddly shaped tank and I want to split it so I can add another Betta. This makes me wish I hadn't given away my 10 gallon tank a couple months ago though... oh well.

     Anyways, I had no real point to this comment. I just wanted to thank you for the ideas. I saw a Betta at Wally World that I want. Most of them looked very sickly though. *sigh* Do you have any suggestions on a better place to buy a Betta? Petsmart's seemed okay and I know there is a Petsupermarket nearby. Btw, your tank looks really great! :)

    2 replies

    Reply 4 years ago on Step 3

    I actually have two Bettas that I bought from Wally World. They'd be the only fish I would actually buy from there. The first one I bought had a bit of fin rot, but seemed feisty. I brought him home, quarantined him, and now he's having massive fin regrowth, and is living happily with a mystery snail and his pet moss ball. The second one was the only healthy Betta at the store when I went in, and is fairly young. He's still being quarantined before I move him to a bigger tank. It's a really nice feeling to bring a sick or maltreated Betta to complete health, but it takes time and effort.

    Major pet stores don't keep the Betta conditions much better than Wally World, so if you really want quality, go to a mom and pop shop, or order from a reputable breeder.

    *I know this is an old comment, but I posted this for future readers.*


    Reply 9 years ago on Step 3


    Thanks for the positive comments !

    I actually got mine at Wal-Mart...  One tip that I got from a small pet store:  Get a male betta that isn't big and flowery.  The fancier they are, the older they are.  If you get a smaller one that almost looks like a female, you will get to see it grow and get bigger due to your efforts !  Another tip that has been working for me:  I pre-soak the pellets before putting them in for the fish.  One of my betta's got a bloated belly from hogging down the mostly dry pellets, but since I've been pre-soaking them (in a thoroughly cleaned plastic soda bottle cap), that problem has never happened again.  I just dip a little of the tank water into the cap, place the pellets in the cap for a couple of minutes, then suck them up with an eyedropper and pop them in for each betta.

    You may be able to use my divider method in your hexagon tank, depending on its width.  You can cut the piece as long as you want ..
    An alternative would be to get a piece of plexiglass cut to the width and height that you need, then drill and de-burr it yourself.  The clear divider may or may not work, though, depending on how aggressive your fish are.


    10 years ago on Step 3

    how did you set up your filter? I tried the divider thing because I had a female that was VERY aggressive and the other female was passive ... or ... terrified. my divider appears to be the same brand or whatever but isn't clear it is opaque. So anyway ... I do have and use a powered filter but even though the divider is perforated it only filters one side well. Actually I once had a pair that successfully spawned and hatched a brood in an undivided 10 gallon tank with a powered filter. .. with no "spawning leaf" or other apparatus to boot ... they also had a tankmate .. a "fresh water lobster" whatever that is LOL