Originally Posted by Bombalurina
Yes, bettas and gouramis will fight - they are both from the anabantoid family and too closely related to co-exist. :)
Just a note: clown loaches get a foot long and need schools of six, so I hope you have a very large tank for them to go into soon! :)
I've owned clowns for years; the 10 gallon is only while they are very small. I have another large tank that they will move into eventually.
I know betta and gouramis are closely related, but read conflicting info online about if they will fight. Having had both dwarfs and regular gouramis, the dwarfs are more peaceful.