Hi
Give him time and he eventually will build a nest.
Males will always flare at their own kind no matter the sex lol keep the water in the low eighties and give them lots of food .Live food is excellant but frozen will do.
i used a 10 gallon tank half full. kepthe female in a hurricane lamp shade. The glass kind that are open on both ends This way the male can always see but can't harm the female. This way when spawning time comes you can just lift the shade. be sure to remove her as soon as spawning is complete. After the fry become free swimming you can remove the male and begin filling the tank. Be sure to keep it covered to keep the air humid and warm.
The fry are very tiny and require microworms or infusoria for about a week.
gary