first of all, the ten gallon is not big enough for just the moor. and seond- in terms of basic needs, bettas and goldfish are not compatible. they have different temperature needs and goldfish are very messy. as for the fighting, bettas seen to percieve anything with comparable finnage or coloring as a threat, as another betta in their territory basically. I would encourage you to separate them, either find the moor a home or an appropriate tank, and get the betta a heater.