Aggressive Male Swordtail!

[clmarlar]

Just got a new ten gal tropical tank. I have 9 fish in it. There is a male rainbow shark, red male swordtail, two black lyretail mollies, a female sunset platy, two other lyretail male mollies, a veiltail betta (not sure if it is male or female), and a redtail variatus ( not sure if it is male or female). The rainbow shark has been in there the longest. The swordtail was in there with him before along with a few others. I just added the female platy and a few other fish. Now the swordtail is attacking my rainbow shark and is acting weird with the female platy. Is he being aggressive now that the female platy is in the tank? What should I do?

 

[techen]

I dont know myself but thats a few fish stuffed into a small tank is it not? Maybe its stress related that hes now attacking other fish.

 

[sebn]

Tank is overstocked, shark needs a MUCH bigger tank http://www.seriouslyfish.com/species/epalzeorhynchos-frenatum/

 

[clmarlar]

Yeah I thought about picking up a 20 gal. Thank you for your advice.

 

[SombreroBanana]

Rainbow sharks need a minimum of 50 gallons, and they should be kept in groups of 6 or more.