Betta fish with others?

Question

I have a couple of fish tanks and today a couple of fish died. They had no tail or fins left, as if they had been picked at. I checked the water and everything was normal. I know they didn't have any diseases because the water had been treated just incase...and no new fish have been introduced. Both of the fish were guppies. Is it possible that the betta fish killed them?

I did do a partial water change recently with water that had been through reverse osmosis...my water has a high buffering capacity and its impossible to get the ph down right now.

I haven't seen the betta fight with the other fish or even blow up at them. One of them did have some nips at the tail. I'm not sure if the betta fish killed him or picked at him after it was dead.

I don't think the medication killed the fish...that was a couple weeks ago and was advised by a marine biologist who works at a state aquarium.

Answer 1

Actually guppies are more likely to pick on each other than for it to have been the betta. Odds are good that the damage occured after the fishes death and that the two things are unrelated. As to the cause of death, that would be anyone's guess. Most likely some type of disease as you can not treat to remove all disease from a tank, that's just an impossibilty.

MM

Answer 2

Did you just notice the fins after they died? Or have they looked frayed before this? If so it is possible it is fin rot. Which happens when the fish live in dirty water. If the water is left unchanged, their own feces and uneaten food particles begin to break down, causing fish to become stressed and more susceptible to the bacteria naturally present in their tanks that causes fin rot. The best measure against this is to always keep your tanks clean. Fin and Tail Rot is a bacterial illness, so you will want to make sure your medication is intended for this purpose.
One medication that is often used is Jungle Fungus Eliminator. For 1 gallon of water, use 1/4 teaspoon. For 2 gallons, 1/2 teaspoon and so forth. Treat the tank for 4 days then do a complete water change. If fin rot is still present, repeat dosage. Other common medications that have been successfully used are Tetracycline, Maracyn and Maracyn-Two combined together, along with sulfa-containing medications.

I don't think the Betta did this because usually Betta's are only aggressive to other Betta's. I would do a partial water change and then clean the gravel using a gravel cleaner. Then medicate with bacterial medication.

**Edit** I read a fellow posters reply below and they state you shouldn't put Betta's in with large tailed colorful fish. My swordtails are very colorful and have larger tails and they have been with my Betta for the past 3 months except for the 4-6 days while breeding and there have been no problems. No nipping of the fins at all! So I will have to disagree with the other poster from my experience.

Answer 3

male bettas will pick on guppies because of their glorious tail...most fish will actually pick on guppies tails, even other guppies. you said you do regular water changes....only take 25% of the water out every 7 days, and add in 25% new water, remember one inch of fish per gallon, especially tropical fish, they should have 2 gallons per inch.... the water should be around 72-78 degrees and you should have a heater and filter. the betta fish didnt kill them...but they all were prolly nipping on each other. bettas go great with any kind of community tetras,,,and swordtails, and mollies, and platys,,and danios. guppies tend to aggrivate any kind of fish....so maybe have just the guppies. and a tank of the other ifsh.

OH and PS, placing a mirror next to the betta causing severe stress and mental anguish leading to many problems like lowered immunity to any and all conditions and illness and stress that will kill it.. anyone that recomends that knows nothing about fish!

Answer 4

How long have you had all the fish living together like that? Do you have other fish in that same tank?

I know that male bettas are capable of doing that to other fish. If you have other fish, it's also possible that your guppies died and they started to munch on them.

I'd recommend taking the betta out and putting it in isolation just as a precaution. Also, observe if other fish die this way after the betta is out.

Answer 5

It is very possible that the Betta killed the Guppies.

He might of mistaken the Guppies for another Betta.


ßübblëš

Answer 6

You know, the very same thing happened to the guppies that I bought yesterday. Except in my case, it was a school of two dozen Tiger Barbs that did the deed.
As for your question, I think I may know the answer.

Bettas, or Thai Fighting Fish, are quite peaceful fish, but please remember that they have been through centuries of selective breeding for their fighting potential. Bettas just *LOVE* to nip and bite fish that have big tails... ESPECIALLY big, colorful tails... If you ask me, bettas should be kept either alone (in a sufficiently sized tank, of course...) or with faster, larger fish that doesn't have colorful tails... Like mollies and swordtails...Never mix two bettas in one tank, unless you want one of them dead by mid-morning.

>>EDIT<<

Well, experiences are subjective, aren't they? Please don't get angry, but what I said was that you CAN place bettas and swordtails together. Please read it carefully. And while I do have colorful swordtails, most of my swordtails are just the regular red-with-black-sword types.

Answer 7

Bettas have big tempers. If fins were nipped at, my best guess would be that the betta's the culprit. I personally saw my betta swallow a guppy whole. Didn't think it was physically possible, but I saw it with my own eyes. it nipped at it's fin until it couldn't swim properly, then swallowed him.

Answer 8

Male betta's generally do NOT like long tailed or brightly coloured guppies. It is highly possible.

It is also possible you lost them because you medicated the water when there was no disease present. Taking drugs when you don't need them can and often will, make you sick.

Answer 9

A Betta will nip at smaller/slower fish.

Also, if your guppies should breed, the betta will gobble up the fry (babies).

Off topic: For a little fun, place a mirror directly in front of your Betta and see what happens.

;)

Answer 10

I have guppies in with male bettas, 5g tanks. I learned that if you try to add fish with a betta in a smaller tank the betta will be aggressive to them.

I have a betta in my 20g tank full of shrimps, danios and tetras and he never bothers anything. He is the "Lord of the Wisteria Forest" and its funny to watch him patrol it. As long as they have space they tend to be great community fish