It's just the general aggresion sequence, Ideally most of the fish I mentioned don't get any aggsion showed to or released. While as the fish you suggested are colorful, long finned, and that's what leads a male Betta to think that it's another make Betta in its territory, there are most likely bettas that will exept that type of fish. But mostly the general amount of aggresion showed from a Betta will be directed negatively towards that fish. I would never recommend that type of fish for a tank with a male Betta, there are also lots of contributing factors to think about when it comes to compatibility, you would need a daily larger, heavily planted, dimly lit tank to keep that combination with your average Betta. Also, from experience on keeping multiple bettas in multiple community setups with a varying, broad range of fish. I've found make bettas boot be typically aggresive towards fish with similar characteristics concerning the fish you recommended
And PS, just Becasue someone else said it, it doesn't mean it's true
The only fish with long fins is the threadfin. Their fins are almost always down anyways, those are just displays. Furcata and gertrudae are pretty plain imo. Neons and endlers are much brighter fish that are the same size and activity level.
And someone keeps them successfully on here.
Someone on here successfully keeps females and male bettas together, yet this isn't usually advised. It most likely won't work, neither will The rainbows, they are notoriously colorful fish, In My Experience. And aren't that dull. They have much more colors than my neons, and endlers, and any that I have seen. Also, I have successfully kept guppies and bettas together, they do fine, yet gennerally they don't so it's not advised. Very similar to this situation, I have very rarely heard that rainbows are okay with bettas (from you) and the rest of the time it's just a general experience and opinion that they don't do well together
So many people recommended them to me D:
Setting me up for disaster.
I really don't see colour on furcata and gertrudae. A fanned out gertrudae, maybe, but blue eyes? o-o Just some yellow, and a grey blue. Neons and endler's are tres colourful, red, blue, orange..
If many experienced fish keepers have recommended them then go for it, I mean, I barely have any experience so I wouldn't know. Lol. They just seem to be the type of fish that wouldn't be compatible. While they might have fewer colors than endelrs and neons, they do seem to be a bit more bright and vivid which leads another male to believe its a threat
Furcata or forktail blue-eyes are pretty boisterous and slightly aggressive to each other in my experience (I had a school of 10 in a 3ft tank). They remind me a lot of danios, just not as nippy.
Even my gentle honey blue-eye males spar a lot and I'm not sure if all that movement and colour would be stressful to a betta or not. Threadfin males will also spar quite frequently and with the size of their fins when spread, I'm not entirely convinced a betta won't be tempted to take a chomp.
I have a 10 gallon tank (temporary as their original tank hit cycling issues) with 7 honey blue-eyes in it and they are a constant hum of activity. I suppose the success of any tankmate is going to depend on the personality of your betta. I'm sure some would be stressed out by the presence of such active tankmates, but likewise I am sure there are some that just won't care.
Also threadfin rainbowfish and spotted blue-eyes are softwater rainbows. I'm fairly certain forktails don't mind harder water.
Hmm it says 5-12dH on seriously fish for both, which I thought 9-12dH was decently hard water.
I also figured that 20 gallons is plenty of room for these fish and would give a betta lots of breathing room.
Here are my 2 cents...
I got 2 labeled female bettas from petco and put them in my 29g planted community tank...then we began to notice that the little pale one was getting darker blue, and very long anal fins...she was a he...a beautiful half moon blue butterfly w/ glorious long fins that rival the Thai bettas! Due to shortage of tanks, I left him in my community while the girl was moved to a sorority...
He is not shy, goes anywhere he, mostly ignores other fish and they ignore him. His tank mates include: pair of Bosemani rainbows, pair of Australian rainbows, 2 clown loaches, 2 big Molly males and some of their kicks offspring, and 4 Cory cats! Each species stays w/its own, no one chases anybody (except mollies), at meal times their is frenzy but everyone eats and no one is overly picked on!
And yes...I know tank is way overstocked but I'm saving for a 50g. I got a 5g that I originally thought to put Sapphire, this male betta, in but I realized that, other than the mollies, he likes other fish and they him...