Fish in breeding box

So I just moved two of my pregnant fish into a breeding box. Let me be perfectly honest. I don't like the breeding box at all. My largest issue is the way it attaches to the tank - Which is to say it hardly attaches at all. I have half a mind to just weigh it down to the bottom of the tank and secure the lid on it tightly. As it is I wouldn't be shocked to find it sitting at the bottom of the tank in the morning with nothing in it.

My other problem with the breeder box is it is tiny, which I suppose is a issue with most or at least nearly most breeding boxes. Right now I have 2 pregnant fish in the box together. I have two more roaming free in the tank. I just could not bring myself to put all 4 into the same breeder box even though it is designed to hold at least that many fish.

I guess it is actually kind of good that I don't want to put all 4 fish into the box. This way I will see what works best. If in 30 days my free roaming fish's fry live then I will know that I don't have to use this silly box ever again.

Oh and one other thing. Trying to catch 1 much less 4 swordtails in a 90 gallon tank... Ya... It's not easy what so ever.