Q: My sister has a 2 year old pet store betta. Ever since we bought him, he has been quite aggressive (he lives alone) and if you stick your hand in his tank, he will BITE it!!!!!! Is biting a normal behavior for bettas?

above question submitted by anonymous reader, Rockford - IL

Grouchy, grouchy, grouchy. That's what bettas are: GROUCHY. ;)

Or is it: Hungry, hungry, hungry. That's what bettas are: HUNGRY. ;)

Grouchy? Hungry? or Hungry Grouches? Or... (Agh my head! It hurts! Make it stop!!!!!)... Oh, who the heck knows. One thing for sure though: Bettas will be bettas. And yes, many do bite. :)

I once saw a man come out of my fishroom with 4 bettas latched on to his jugular. He was in a total panic: Yelling, kicking, screaming, running, trying to pry them off but OH NO they would not let go, like a bunch mini bulldogs hanging from his neck line HAHA! Blood skirting everywhere and stuff... I told him not to go in. "Dangerous" I said. Of course the big tough fellah' wouldn't listen. "Well, how dangerous can a little fish be?" he said.

Well now he had found out. Cause see, we are not just talking about ANY little fish here. We are talking about Siamese FIGHTING Fish  hehehe.

OK. SO, maybe I am exaggerating a little... OK, a LOT. I was just pulling your leg about the bettas latched on to his jugular and stuff (but I had you going there for a moment, didn't I? :) ). WHY? Because bettas look convincingly intimidating hehe. So it wasn't a big stretch of your imagination to actually visualize 4 bettas taking on a mere mortal human. 

Now let's comment on the real truth. Do some bettas bite? Yes. Do all bettas bite? No. Do bettas bite because they are mean? No. (At least I don't think so). So why do they bite?

There are two reasons why a betta may bite a finger or any foreign object that enters his little aquatic kingdom:

  • bettas are voracious: In fact they are hungry 24/7 or just about. They can eat LAAARGE quantities of food, to the point of not being able to swim anymore. YES, I am SERIOUS. This is NOT a joke. 
    fat fry.JPG (95292 bytes)I have seen young bettas eat so much their bellies had more than tripled in size (see left) and now they were all at the bottom, lying on their round bellies, unable to swim. In short, the little guys just don't have any self restrains and just don't know when to STOP eating :)... (Mmmm.. Sounds like Mr.181 when it comes to chocolate eclair HAHA!)  As a result, they look for food also 24/7 and anything that pops into their tank is immediately tasted :), including, but not limited to: fingers, forearms and arms. Well, I have never submerged my head in a tank filled with bettas (actually surprising, cause I'm sure many of you would have thought I had LOL). If I did, one day, go bizurk and decided to stick my head in a betta grow out tank, I am fairly sure that it would be thoroughly investigated, sized up, examined and, yes, sampled LOL. I am sure the tip of my nose would get it first.... Mmmmm.... (betta nose surgery? Maybe the way of the future? LOL. I can see it from here: "Try our new, ALL natural, plastic surgery"... Could be making tons of money!!! hehe). OK Faith, back to earth. When they nip you, bettas do not really hurt at all. Unless there is 60 of them and one tender under arm spot, that is. OUCH! I have had to pull out my arm pronto a few times in the past. I hate that. You know. Backing down. Bettas sense that I am no longer the "master" and start coping nasty little attitudes. Very dangerous LOL. So I took the habit of using a stool and whip anytime I clean betta tanks now LOL. Gotta show them how's the boss! (yop, you've guessed it, that was a JOKE again - I just like to keep you on your toes, that's all ;)  ). The part about pulling my arm out pronto was true though :). What it feels like basically is little needles pricking you. Nothing major, no blood shed or anything, just not very pleasant, that's all. I am sure that should I fall asleep with my arm in the tank, (and I'm actually surprised that too, has never happened LOL, considering how often I work in the fishroom until the wheeeeee hours of the night) the bettas would eventually have all tried to eat it, realized it was not eatable (or tasted bad LOL) and would no longer be interested in biting it.
  • bettas like dominating. In their attempt to dominate, they will perceive a finger (or any intruder) as a rival and attack it. In that case, the betta would probably bite it over and over again, and keep going for quite sometime. He may flare at it, display for it and basically act towards it like he would towards a rival betta. 

In short you could try an experiment. Pull up a chair, make yourself comfortable (a newspaper to read and also a First Aid kit LOL might be advisable), and stick your (clean) finger in his tank. Then simply sit and wait. See what he does after a while. Does he simply swim away and show no more interest after a few bites? Then he was mistaking your finger for food. Does he keep attacking it, does he flare, does he display for it over and over again? Then he is mistaking it for a rival.


AS A MATTER OF FACT LET US ALL DO THAT EXPERIMENT. I want you all to pick one betta and slowly put your entire index finger (but not your hand) in your betta's tank or bowl. Keep it there for 5 whole min if you can. I want you guys to share your result with us by taking the first poll below:

One hour later, let us all repeat the SAME experiment with the SAME betta. Let us see if the behavior changes the second time around (aka: do betta learn?). Share your results by taking the second poll below.

I am curious to see what we will find out :))). And together, we can answer your question "Is biting a normal behavior for bettas" with much accuracy :). Ooooo, fun fun fun! This is going to be exciting!  And remember, before your stick your finger in there (just the finger please, not the whole hand) make sure it is clean and very well rinsed. And once you are done, wash your hands kiddos!



what does your betta do when you put your fingers in his bowl/jar/tank ?


ignores it completely 
swims to it to check it out once, then ignores it is friendly towards my fingers and keeps playing with it is scared by my finger and darts away/hides away takes a couple bites at it to 'taste' it then swims away keeps biting it, flaring at it and acts aggressively towards it  




When you repeated the experiment, did your betta:


have the same reaction the second time around did not have the same reaction the second time around  


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About me

I am a member of the IBC, founder and President of LABS  (Los Angeles Betta Society) and have been helping the betta community through this website since 1998. 
I have over 
175  spawns and  3500 shipments under my belt and have been featured on national and international television.       
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