What's Your Experience with Divided Betta Tanks?

Hi friends! Some of you may know that I rescue, rehabilitate, and foster betta fish. Over the past 11 years I've used small, 1G temporary tanks to house the fosters in until they can get adopted. Unfortunately, over time, and no thanks to my location, there are less and less fish enthusiasts, and some of these fosters are here for 3 months or more! The longest foster was in my care for 8 months! I feed a wide variety of foods including frozen & live, but I just don't like using small, 1-3 gal (4-13 litre) tanks for my fosters. So instead, I plan to continue my 2.5 gal/9.5 litre rehab tanks but use divided 10g/38l tanks for the fosters.

Here's my question - in over 11 years of keeping bettas, never have I kept divided tanks. I've heard great things about them like using only 1 sponge filter & heater, but I've also heard that them being able to sense one another's pheromones is a big, stressful experience. I rescue fish so they avoid those stressful situations! I couldn't stand to be the one causing them...and my oldest betta was 8 years old. I wouldn't want to decrease anyone's lifespan when I'm trying to save them from it!

I want to know is, for those of you experienced with divided betta tanks of preferably 5-10 gals or 19-38 litres, how did/do they work for you?

Pictures, honest opinions, questions, concerns, constructive criticism, comments, support, and all other kind interactions me or anyone else on this thread are welcome!

 

I did a 20 gallon long with 3 dividers. The dividers were black, not see through, but did have holes in them for water circulation. I also had a sponge on each end of the tank and a heater on each end.
The biggest issue was they would figure out how to get over to the other side.
They flared if they thought they say another fish.
Otherwise, if you seal each section off, they are independent tanks and I'm not sure you solve having one tank with dividers. The dividers I used are very nice, but small fish can figure out a way around them occasionally.
Here's the divider I used:
Ebay tank divider

 

Just finished wrestling with this question for exactly the same reasons. I've taken in surrendered "fair fish" bettas & goldies for 20 some years & attempted division for the 1st time recently - after a great deal of research, chats with hobbyists, breeders & a piscene vet. For the record, there was little to no support for single tank division as long-term housing.

To be brief, I divided a 20 g long with DIY tight fitting opaque mesh dividers - originally for 3 compartments, then shortly after they went in, re-adjusted for 2 compartments. Heavy planting & hardscape against the mesh to further the division. A low flow hob centred & sponge filters in the ends.

Bottom line, the stress of these fish - even two who had peacefully co-existed whilst continuously breaking thru the commercial divider on a 3 g hospital tank - was over the top phenomenal. They knew there was another betta next door.

One was removed instantly because he was frenzied. Then I tried the 2 who had previously co-existed peacefully in the tiny hospital tank - undivided. A divider went down & even divided into two 10 g spaces, one male spent every second trying to find a way around, risking damage to his face, fins & general health I thought, to get to the other fish.

The marbled fish next door, hid. That's it. He hid at the farthest reaches of that divided 20 g long, knowing the other betta was in the tank, somewhere, even tho he couldn't see him. Their behaviours told me all I wanted to know about the strength of stress hormones in betta regardless of behaviour.

To me, it was not worth their health to keep them in a divided tank. I know the difficulty of having a ton of rescues in individual tanks & the hope that divided tanks will be the answer. I also know the amount of work that goes into setting up a divided tank & failing. It's brutal.

Like you, I work hard to bring these often mangled, infection-ridden bettas to health & to re-home them. The few I've kept permanently, tend to live on average 5 years. I can't see bettas living in a divided tank, sharing hormone-spiked water, living that long.

Fortunately, my foolish experiments to make co-existing & then a divided tank work, did not end in any deaths. Ultimately, I drove 4 hours round trip to re-home the 2 healthiest bettas with a breeder & have the submissive male in the 20 g long with corys. He seems to be regaining health & confidence.

There are those who may disagree with me, having kept multiple male bettas in divided tanks to their satisfaction. My recommendation remains the same; no divided tanks for betta males. I believe the risk to the health we have worked so hard to improve is too high.

I wish there were a better answer. Re-homing networks dry up & very long-term foster or permanent ownership becomes the default. It's tough to be the fish guy no longer taking in betta surrenders, but I'm finding that's the long term answer for me. Perhaps it is for you too.

Best of luck on the journey!

 

I tried a divided Betta tank once, I do not think it works very well. The fish could see each other through the small holes in the divider and it seems they never got used to each other. I think it causes unnecessary stress, which now seems like it should be obvious to me. Keeping two highly territorial fish in close proximity does not seem like a good idea.

 

aquanata Lucas35 - honestly, those are kind of the answers I was looking for. If it'd work out, great. But I take in a variety of bettas; depressed, stressed, sick, injured, even ones afraid of hands (I have one like that right now - poor fish.)

What you mentioned aquanata is what I expected. I could never see bettas in divided tanks living long, but I had no evidence to back up this hypothesis.

I'm grateful for both of your inputs - it's very helpful, and I'm sure will save many fish's lives!
A question aquanata ; why do so many people say bettas in divided tanks don't notice a fish on the other side? Do you think they just happen to be submissive bettas or what?

When I was 10 years old I had a 12 gal bowfront with 2 males and a female. Weird, right? I guess it's because the original betta was 5 years old at the time (a blue grizzle combtail named Ghast), and the pair (orange pineapple butterfly veiltail named Fox and royal blue hmpk female named Blueberry) would became extremely depressed if I ever separated them which, trust me, I tried. It also had rescue skirt tetras, tiger barbs, and a variatus platy! I admit I was far less experienced than I am now (this was 11 years ago and didn't even know about the nitrogen cycle at the time) but this is still my favorite tank I've had to date

 

"A question aquanata ; why do so many people say bettas in divided tanks don't notice a fish on the other side? Do you think they just happen to be submissive bettas or what?"

Sorry it's taken me so long to reply. I know folks report that their bettas don't notice other bettas in a divided tank but I suspect they do. Ever been trapped in a place with a really awful smell you were unable to escape & your gut told you making a scene wasn't going to help? You just plowed thru as calmly as you could - tried not to breathe in that shared elevator? Instinct & perhaps manners kicked in - aggression was gonna wear you out more than gritting your teeth. I suspect our oh-so-responsive bettas do exactly the same. They're 'submissive' & not aggressing as I described the one, because their instincts gauge submission as the best means of survival. They hold their breath the *whole* elevator ride & it wears on them.

Given the high-aggression behaviour of 2 of the betta & the cowering of the third, it seemed to me that whatever hormones were being infused into that water, they had to be massively powerful to elicit such extreme behaviour at both ends of the spectrum. Constantly enduring either hormone elicited aggression or hormone elicited fear would wear me right the heck out. I'd guess it wears out a smarter-than-most-believe betta pretty quick too.

Ah - our 1st tanks. My own were some time ago well before most hobbyists knew anything about establishing a nitrogen cycle & live plants were a rare thing. Mine however were filled with everything that came out of a pond plus goldfish. I was devastated when I found out that while minnows could escape turtles in a big tank, goldfish could not. I've been paying for my childhood aquaria sins ever since, taking in goldies & betta.

 

When I imported fish, we had a Betta Hotel. Three layers high, each compartment around two liters, five hundred compartments in total. The fish generally stuck to their own space. They were in the Hotel for six weeks and got used to each other over that time.

 

"A question aquanata ; why do so many people say bettas in divided tanks don't notice a fish on the other side? Do you think they just happen to be submissive bettas or what?"

Sorry it's taken me so long to reply. I know folks report that their bettas don't notice other bettas in a divided tank but I suspect they do. Ever been trapped in a place with a really awful smell you were unable to escape & your gut told you making a scene wasn't going to help? You just plowed thru as calmly as you could - tried not to breathe in that shared elevator? Instinct & perhaps manners kicked in - aggression was gonna wear you out more than gritting your teeth. I suspect our oh-so-responsive bettas do exactly the same. They're 'submissive' & not aggressing as I described the one, because their instincts gauge submission as the best means of survival. They hold their breath the *whole* elevator ride & it wears on them.

Amazing answer, thanks!

Given the high-aggression behaviour of 2 of the betta & the cowering of the third, it seemed to me that whatever hormones were being infused into that water, they had to be massively powerful to elicit such extreme behaviour at both ends of the spectrum. Constantly enduring either hormone elicited aggression or hormone elicited fear would wear me right the heck out. I'd guess it wears out a smarter-than-most-believe betta pretty quick too.

Ah - our 1st tanks. My own were some time ago well before most hobbyists knew anything about establishing a nitrogen cycle & live plants were a rare thing. Mine however were filled with everything that came out of a pond plus goldfish. I was devastated when I found out that while minnows could escape turtles in a big tank, goldfish could not. I've been paying for my childhood aquaria sins ever since, taking in goldies & betta.

...this wasn't my first tank.

"My" first tank was a 15 gallon that my dad had gifted me along with 5 young feeder goldfish. I politely told him that these fish get MASSIVE, so we returned them to the store. Then he accidentally broke the tank. Being so young I was devastated, so my mom gifted me a 29 gal for my carnival goldfish Tip and feeder goldfish Carp. I knew a bit about fish because I did research at 8 years old in a hospital getting chemotherapy for an extremely rare kidney disease. Don't worry I'm fine now

My first "tank" was a 4 gal shoe bin for my very first personal fish, Bluestar; a turquoise & royal blue roundtail female betta. I knew they needed at least 5 gallons so I got what I could afford at the time. I was maybe 8 years old at the time? I got her for my birthday with a red veiltail female who ended up dying soon after from what I think was stress (yeah, I'm sure you can guess why...) Though I started off better than most, I knew of the nitrogen cycle at 11 when my brother's betta, a blue male halfmoon, had symptoms of nitrite poisoning. Since then I've bought my own pet or fish supplies with little exception. Unfortunately, that was 2 years AFTER I kept that overstocked, weirdly peaceful tank.

Oh yeah, and don't worry about Tip and Carp. I got a 75 gal for christmas one year so they got moved into that. Eventually I got a 90 gal and a Fluval FX4 for free from a guy who brought me his old goldfish. They died soon after so Tip & Carp lived the rest of their years in it (sadly only 9 years due to overdosing of Prime.) Tip only got 8" long but Carp got 13"!

When I imported fish, we had a Betta Hotel. Three layers high, each compartment around two liters, five hundred compartments in total. The fish generally stuck to their own space. They were in the Hotel for six weeks and got used to each other over that time.

Really? They didn't show any signs of stress?

Then again they were only in there for a few weeks

 

Amazing answer, thanks!

...this wasn't my first tank.

"My" first tank was a 15 gallon that my dad had gifted me along with 5 young feeder goldfish. I politely told him that these fish get MASSIVE, so we returned them to the store. Then he accidentally broke the tank. Being so young I was devastated, so my mom gifted me a 29 gal for my carnival goldfish Tip and feeder goldfish Carp. I knew a bit about fish because I did research at 8 years old in a hospital getting chemotherapy for an extremely rare kidney disease. Don't worry I'm fine now

My first "tank" was a 4 gal shoe bin for my very first personal fish, Bluestar; a turquoise & royal blue roundtail female betta. I knew they needed at least 5 gallons so I got what I could afford at the time. I was maybe 8 years old at the time? I got her for my birthday with a red veiltail female who ended up dying soon after from what I think was stress (yeah, I'm sure you can guess why...) Though I started off better than most, I knew of the nitrogen cycle at 11 when my brother's betta, a blue male halfmoon, had symptoms of nitrite poisoning. Since then I've bought my own pet or fish supplies with little exception. Unfortunately, that was 2 years AFTER I kept that overstocked, weirdly peaceful tank.

Oh yeah, and don't worry about Tip and Carp. I got a 75 gal for christmas one year so they got moved into that. Eventually I got a 90 gal and a Fluval FX4 for free from a guy who brought me his old goldfish. They died soon after so Tip & Carp lived the rest of their years in it (sadly only 9 years due to overdosing of Prime.) Tip only got 8" long but Carp got 13"!

Really? They didn't show any signs of stress?

Then again they were only in there for a few weeks

What happened with this system was that altough the fish were happy enough we decided that we had some hormone issues because they were sharing the same water, we eventually went back to the individual 4 liter jars.

 

"My first "tank" was a 4 gal shoe bin for my very first personal fish, Bluestar; a turquoise & royal blue roundtail female betta. I knew they needed at least 5 gallons so I got what I could afford at the time. I was maybe 8 years old at the time? I got her for my birthday with a red veiltail female who ended up dying soon after from what I think was stress (yeah, I'm sure you can guess why...) Though I started off better than most, I knew of the nitrogen cycle at 11 when my brother's betta, a blue male halfmoon, had symptoms of nitrite poisoning. Since then I've bought my own pet or fish supplies with little exception. Unfortunately, that was 2 years AFTER I kept that overstocked, weirdly peaceful tank."

You really did start off well JustaFishServant! If it's true confessions time, I was nowhere as educated as you were. Early 70's. My mom installed a 25 g above the kitchen sink & when she tired of it, handed it off to me, 5 yrs & my 4 yr old brother who had our rooms filled with big tupperware ponds & shoeboxes of insects, fledglings, mice .... you name it. We were basically "free-range" kids who disappeared into the woods at dawn & re-emerged at dinner with bags & tubs of 'stuff'. We had no idea what we were doing - just feeling our way along like any pre-schooler.

Mom provided us with the tank, her 3 goldfish & a jar of goldfish flakes. That's it. We'd set up chairs, climb up & change that water day after day. The 1st three goldfish died pretty quickly. She replaced them. We eventually found one of the goldfish eating its two compatriots & thought we had a cannibal goldfish. Mom threw in 2 more. Weeks later, found a lone goldfish with 2 skeletons. So we got the bright idea of putting that goldfish into one of the turtle ponds where it'd be 'safe' & found out right quick how fast a turtle can eat a bloated, slow moving goldfish. But mom liked the animals above the sink, so for years until we moved out she had goldfish in there we had to keep alive.

Didn't get my own 'proper' tanks until adulthood & while I knew enough to keep betta in actual separate tanks I didn't know much else about aquaria. Never occurred to me that there was more to it than clean water & food, even after running multiple tanks from small to 120 g for years & with a huge library of aquaria books. Changed out hundreds of gallons weekly & scrubbed out those filters for years. No ick, HTH, fin-rot, etc... either except in the surrenders I began to get pretty early on. I figured 2-5 yrs on the basic danio, tetras, betta the LFS sold & rehomed much longer lived goldies & plecos to private ponds until I built my own.

My area didn't get reliable internet until about 2010 so that's when I began learning about the nitrogen cycle & the dirted tanks I run now. Building my own ponds too. Suddenly had access to other hobbyists & fish I'd never kept before. Lifespans in my tanks increased significantly & fish keeping became much more absorbing, as well as less labour intensive.

I can't say I did my earliest aquatic animals any favours & up till 2010 probably shortened a lot of fish lives in clean but uncycled tanks. Internet access & everything available online has made a huge difference to hobbyists & the animals we keep. I enjoy seeing people like you starting out with far more info than I had & turning that into experience & life long, successful, fish keeping. Eventually I hope it'll be animal keepers like you & others here, who make the betta in a bowl & unethical trade practices things of the past.

 

Wow aquanata - great story!

Internet access & everything available online has made a huge difference to hobbyists & the animals we keep. I enjoy seeing people like you starting out with far more info than I had & turning that into experience & life long, successful, fish keeping. Eventually I hope it'll be animal keepers like you & others here, who make the betta in a bowl & unethical trade practices things of the past.

Thanks for the complements! I agree; that's why it's annoying when people DON'T research pets before. How long does it take to look up something? 10-20 seconds?

At the time, I didn't know much about fish without a phone. I used my parent's when I could researching for hours at a time. I have one now though which is good since I can talk to awesome fellow fish lovers like you