Female Betta in a mixed fish community tank

hi,
I currently have 2 female bettas in a 20 gallon heavily planets community tank with mollies, corydoras and 3 guppies. So far the girls have completely ignored each other. I didn't hear about the rule that there must be 4 in a tank together and i'm not sure if my tank's bioload can take too many more fish. My question is, is that rule only apply when the girls are in a tank with just other bettas. just to add these fish were in a community sorority tank together when I got them and appear to show no aggression to any of the fish, however they have only been in there for 4 hours so far.

 

Where did you hear you must keep 4?

 

you are pretty overstocked as it is with what was in there before the bettas. I don't keep female bettas so I'm not sure about the 4 rule. ive seen others say you need a few for a sorority, though I'm not sure about just adding them to another community tank

 

Usually you need odd numbers of female bettas to keep aggression down with minimum of 5 but 7 is better. Also sorority are usually left as betta only with the exception of corys or pleco. BUT people have been known to make it work with other fish but most of the time it doesn't. Females have aggression period. The reason the numbers work with more is the aggression is distributed among many instead of just one which would kill the fish due to stress, nipped fins, etc. The reason the odd numbers are recommended is because they won't pair up to gang up. If you have 3 for example, 2 will usually gang up and kill the 3rd then fight amongst themselves until the second one dies. When you only have 2, they will fight until one dies. It's possible you could get lucky so I would watch them and if they start showing signs of aggression I would take them out and separate them. Good luck

On a side note, bettas can be really good community fish when there is just one (usually male) in with other fish. The trick is to add the betta after the community is already established.

 

Hi! This entire post is related to female bettas living together.

I think I'm getting what you're saying though about the 4 rule. When it comes to female bettas, it's safest to have 5 or more in a tank, and if each fish needs at least 3 gallons each, then you're looking at a 15 gallon tank minimum. I have kept a betta sorority for three years, and it took me six months to figure out that with my 15 gal tank, I have to always have at least 5 fish in there to monitor aggression levels.

HOWEVER you also need to take into consideration the personalities of each of your bettas. Some of my bettas did fine living in groups of 3 and others hate it (and by hate, I mean they got super aggressive and had to be removed). It depends on the individual fish!

Your case is a bit different: it looks like you have enough fast fish to balance out potential aggression from your bettas. The mollies and guppies are fast, which will help with fin-nipping etc from the bettas (the logic being, if you can't catch em, you can't bite em, and eventually the bettas will get tired of chasing the faster fish around the tank). I found that as long as the other fish aren't super finny (which can be perceived as a threat to a betta fish - yes, even a female one. So don't add an Angel or something slow and fin-heavy), you should be ok in the long-run. As long as your fish are co-habitating well now with no signs of stress from any of them, you should be ok.

Just always be sure to monitor them for any microaggressions etc. Don't let yoru tank go unwatched. Female bettas are also very aggressive when they feel threatened. They also like to establish hierarchies and territories in the tank. When you move decor around, for instance, it can upset that balance, and you may have some temporary aggression. Monitor it, have a quarantine net and tank ready, and you should be good!