75 Gallon Tank Are they breeding?!?! Gourami's

I have three gourami's, over the past few days one has gotten darker in it's breast area. And when I came home today my two blue gourami's were circling each other and putting there head near the other's butt as I've heard mating gourami's do. They also stay at the top of the tank sometimes just gulping air(?) and if not that just pecking at everything in the tank for what I think is an attempt to find more food. I would think this all is breeding behavior but they are about only 2-3 inches and I'm not sure they breed this small. Also, I thought they were all males but I'm not experienced in sexing fish so I might be wrong.

I have three gourami's, over the past few days one has gotten darker in it's breast area. And when I came home today my two blue gourami's were circling each other and putting there head near the other's butt as I've heard mating gourami's do. They also stay at the top of the tank sometimes just gulping air(?) and if not that just pecking at everything in the tank for what I think is an attempt to find more food. I would think this all is breeding behavior but they are about only 2-3 inches and I'm not sure they breed this small. Also, I thought they were all males but I'm not experienced in sexing fish so I might be wrong.

 

Gourami fish make babies like betta fish, if they’re going to successfully breed the male will make a bubble nest at the top of the water.

 

View attachment 733006

 

Gourami fish make babies like betta fish, if they’re going to successfully breed the male will make a bubble nest at the top of the water. View attachment 733007

Will this bubble nest be possible if my filter is on? Or will it wash away

 

turn you filter off just in case it makes life easier. To feed gourami babies here is a video. (pls watch)

 

Will this bubble nest be possible if my filter is on? Or will it wash away

Depends on the filter.
If it’s a hang on the back with a powerful flow the bubble nest won’t stay