Redtail Shark & Mollie Fighting

[czmudzin]

I have a 10 gallon tank and have a few tropical fish in it. Most recently (about 1.5 - 2 months ago) I bought a Balla and a Redtail shark. Everyone in the tank got along, but the Redtail shark got territorial over a column ornament I have in the tank.
 
Recently I noticed my mollie's top fin looking a bit different, like it was torn or something. He was still active, healthy, and eating, so I just checked the chemical levels and the temperature of the tank to make sure everything was ok.
 
This morning, I saw the Redtail shark and the Mollie going at it aggressively, and the Mollie's fins were torn more than before. How can I get them to stop fighting? What Should I do? Any suggestions?
 
Thank you in advance.

 

[Lillefishy]

Your tank is too small for both the shark & the molly
Red tail sharks get more territorial & aggressive as they get older, you should think about either getting a larger 4' tank or rehoming it & the molly.
Edit: just seen you have a Bala too, they need to be in groups in a 6ft+ tank

 

[ech0o]

Firstly, you have fish that will not fit that tank.   10 gallons is WAAAAAAAAAAAAAAAAAAY to small for any of those fish, notice how i emphasize how small as we are not talking "slightly".   Bala sharks require somewhere around an 8' long tank.   Redtail sharks require somewhere around 55 gallon tanks, which is slightly less than a Bala, yet still over 5 times the size of your tank.   The molly is the one that is least of the issue, yet they still require 20+ and some argue even a 30 gallon requirement.
 
Basically, all but one of those fish will soon die from being attacked and killed.  Then soon after, the last one will die from stress from being confined in a space that is much too small for it.
 
I have a few suggestions.   One would be get rid of all 3 fish, and start over with fish that will suit a 10 gallon tank.  Another would be go out and buy somewhere over 120 gallon tank to keep the bala, get rid of the redtail and molly, and start stocking from there.  The last would be get rid of the Bala, get a 50+ gallon tank, keep the molly and the redtail, and start stocking from there.
 
You should do some research before you stick random fish into random sized tanks, go into forums like these and ask questions on stocking possibilities beforehand, so you end up with a good array of fish that will actually work together and in the size tank you have.   When you get rid of these fish let me know if you need help with stocking options, I am putting together a nice planted 10gallon right now and have been researching all the different possibilities.

 

[Ninjouzata]

This tank is way too small for any of the fish you've listed, so that is probably part of why they're fighting. Red tails are pretty territorial but I think that isn't until they get older?
 
Bala's get 14" are quite active and prefer to be kept in groups, need very large tanks, I think the minimum is 8ft (?) but most would rather see them in 10ft+, which either of those are hard for most of us.
It's a shame how easily these are sold
 
The red tail gets 6" and needs 40g minimum, though 55g+ is much better.
 
Mollies need 30g+, as they do get a decent size and are fairly active.
 
I would upgrade your tank ASAP or rehome them and get fish suitable for this size tank. Sorry if that seems harsh

 

[czmudzin]

I just bought these fish based on the suggestions of employees at PetSmart (obviously a mistake in iteself). I didn't realize the sharks got  so big and more teritorial as they grow older. I'm not in a situation where I can upgrade the tank size at the moment.
 
Edit: Will a 30 gallon work? I can upgrade in one month's time.

 

[ech0o]

Negative, a 30 gallon might hold your molly and redtail shark, but you would still have to get rid of the redtail fairly quickly as it would not take long to outgrow a 30, I would honestly take them back to petsmart and demand a refund based on the fact that their employees sold you fish that most people would make jokes about putting into 10 gallon tanks.  They are pretty good about refunds, and they also have many fish that would work in a 10 gallon tank.

My apologies about your petsmart advice, you will come to find through others experiences as well, that petsmart seems to hand out a TONS of "free" advice, that most of the time you take with a grain of salt LOL, their employees say some pretty nutty stuff sometimes!

 

[Ninjouzata]

Really, really recommend taking them back and getting fish suitable for this size tank.
As was said, 30g is too small for the redtail to stay in permanently. The molly would be fine though, and the bala needs to be taken back as well.
 
Most places will be happt to sell you anything for any size tank as they want your money, unfortunately